SpicyNodes is a system for displaying hierarchical data, in which a focus node displays detailed information, and the surrounding nodes represent related information (Focus + Context), with a layout based on radial maps. It has web (Flash) and mobile (iOS) implementations.
SpicyNodes displays a central node, orbited by related (child) nodes. Each child node can be linked to other child nodes. As the user navigates (changes focus) from node to node, a root path traces the path back to the home node. In a typical implementation, only child and ancestor nodes are displayed. When the user browses, nodes appear and disappear, and the layout rearranges to fit. It is a generic method, with uses ranging from dynamic poetry, to mind mapping and concept mapping.
- Visual browsing - Similar to other concept mapping tools, SpicyNodes allows authors to display visual thoughts and links between information, and publish an information map for users to browse.
- Non-linear - Users can jump from node to node, or descend into a tree to find specific information. Since the number of nodes increases exponentially with the number of orbits, a user can find a piece of information in only N clicks/taps, while navigating a space of XN nodes, where X=average nodes per orbit. Conversely, node layouts are inefficient for reading contiguous pieces of content in a linear manner.
- Displays a subset - Only a limited number of nodes can fit on a typical screen at once, which requires a large enough screen to fit the nodes, and means it is usually not possible to display all the nodes simultaneously.
- Balanced branches - Layouts only make sense if there are balanced branches with fewer than two dozen child nodes. A typical implementation requires an average of 2-10 linked/child nodes per node. Too few, and the layout becomes a string of pearls. Too many, and the nodes do not fit.
SpicyNodes is a radial tree layout engine, modified using force-based algorithms, bias controls, and variable pivot point. It also uses an approach similar to hyperbolic trees to reduce sizes far from the focus node. Key aspects of the method are publicly described. The layout is adaptive, changing as the user clicks from node to node, to minimize cluttering. Nodes can contain any content (formatted text, images, videos, etc.) or links to other nodes or content. There is a "focus" node, and users change focus from node to node.
The algorithm was developed by Michael Douma and colleagues at IDEA.org, starting in 2005. The layout algorithm is based on the work of Yee and his associates, and the underlying mechanics have been further described in papers and talks at conferences on Information visualization, on Museums and the Web, and on distance education.
Early implementations include:(a) Genealogical browser of the Greek Gods released March 2006 in the WebExhibits online museum. (b) A master's thesis in 2007. (c) Virtual exhibit navigation, for three online exhibits (e.g., Daylight Saving Time, Calendars, Poetry forms) released in 2008 in the WebExhibits online museum.
Current implementations 
- Web-based - A web-based platform for authoring and publishing node maps. is available as a Software as a service, built on Adobe Flash, provided with both free and paid versions by the original development team at IDEA.org, launched 2009. It has an open API. Received a "Best Website for Teaching and Learning" award in 2011 from American Association of School Librarians (AASL), and voted #edchat's 35 Best Web 2.0 Classroom Tools in 2010. It has been used for presentations in professional conferences and meetings. There are third party guides, reviews regarding general usage, and instructional design. The web implementation allows embedding in a blog, and can also be run as a form of slide show where each node corresponds to a slide.
- Multitouch - The first multitouch implementation of SpicyNodes was as part of the WikiNodes multitouch Wikipedia browser for the Apple iPad, and launched in April 2011.
Related, but different implementations 
For authoring, there are related mind mapping and concept mapping products, such as FreeMind. Typically these do not allow the end user to change focus from node to node. For display, there is analogous software for moving node to node, including: Visual Thesaurus from ThinkMap, TuneGlue, Lexipedia, and Prefuse Flare, and the Discovr apps. (The Discovr app, which also uses radial layouts, with a different layout algorithm which is primarily force-based.)
See also 
- Radial tree - the general type of layout algorithm
- IDEA.org - the organization that researched and developed the method.
- 'Spicy Poetry' in 'OCLC Reveals its Strategy for Library Automation', Smart Libraries Newsletter, American Library Association, Volume XXIX: Number 6 / June 2009. July 13, 2009.
- "Chapter 11: Online Mind Mapping" by Carl Anderson and Richard Byrne." In What School Leaders Need to Know About Digital Technologies and Social Media By Scott McLeod, Chris Lehmann. John Wiley & Sons, Oct 25, 2011.
- W. Ng. 'Can we teach digital natives digital literacy?' Computers & Education 59 (2012) 1065–1078. Published by Elsevier.'
- Carmen Holotescu & Gabriela Grosseck. 'M3-learning - Exploring mobile multimedia microblogging learning'. World Journal on Educational Technology. Vol 3, issue 3 (2011) 168-176. http://www.world-education-center.org/index.php/wjet/article/viewFile/248/pdf_67
- Sheth and Cai. 'Visualizing MeSH Dataset using Radial Tree Layout'. Indiana University, Bloomington. http://iv.slis.indiana.edu/sw/papers/radialtree.pdf
- Science of Science Research and Tools Tutorial #07 of 12 - Dr. Katy Börner http://ivl.cns.iu.edu/km/pres/10-NIH-Tutorial-07.pdf
- Douma, Michael, Greg Ligierko, Ovidiu Ancuta, P. Gritsai, and S. Liu. SpicyNodes: Radial Layout Authoring for the General Public. InfoVis 2009. Atlantic City, NJ. October 2009. Presentation.
- Yee, K.-P, D. Fisher, R. Dhamija, & M. Hearst. “Animated Exploration of Dynamic Graphs with Radial Layout”. Proc. Information Visualization, 43-50, 2001.
- Douma, Michael, et al., Concept Maps for On-line Exhibits: Using SpicyNodes. In J. Trant and D. Bearman (eds). Museums and the Web 2010: Proceedings. Toronto: Archives & Museum Informatics. Published March 31, 2010. http://www.archimuse.com/mw2010/papers/douma/douma.html">http://www.archimuse.com/mw2010/papers/douma . Web.
- Douma, Michael and Joe Romano. Creating Online Mind Maps and Concept Maps. 25th Annual Conference on Distance Teaching & Learning. Madison, WI. 4-7 Aug 2009. Presentation.
- Web site: http://www.webexhibits.org/greekgods/ ; a blog mention: 'A Big Fat Greek Tree' at www.4Kids.org at The University of Kansas. http://www.4kids.org/backissues/2010/4kidsHTML08-22-10/ ; Also used a teaching resource in 'Mythology' taught by Mr. Russell Rice, M.Ed., NBCT, Steilacoom H.S., WA http://mrrice.pbworks.com/w/page/10963312/Mythology
- Michael Felix. "Trellis: a blog-based approach to the development, organization, and visualization of ideas." Masters Thesis. Advisors: Arnold, Chris; Smith, Bret; Lu, Tsai Liu URI: http://hdl.handle.net/10415/932 Date: 2007-08-15
- 'WebExhibits Presents Daylight Savings Time Nodes' 27-Oct-2008. Neat Rox. http://neatgemstones.blogspot.com/2008/10/webexhibits-presents-daylight-savings.html ; Calendar nodes listed in Cornerstones of Science A National Science Literacy Initiative, Brunswick, Maine http://cornerstonesofscience.org/websites-children.aspx
- Virtual exhibits: http://www.webexhibits.org/daylightsaving/nodes.html , http://www.webexhibits.org/calendars/nodes.html & http://www.webexhibits.org/poetry/nodes.html )
- 2011 7th International Conference on IT in Asia (CITA) Interactive Patterns of Interactions for a Mind Mapping Multimedia Courseware Noor Haitham Saleem, Manjit Singh Sidhu, Naser Adnan , Nameer A. Shafeek, Maha.M.Ablahd Yousif
- Children’s Reading of Printed Text and Hypertext with Navigation Overviews: The Role of Comprehension, Sustained Attention, and Visuo-spatial Abilities Ladislao Salmerón & Victoria García ERI Lectura & Department of Developmental and Educational Psychology University of Valencia, Spain
- Spicynodes API at ProgrammableWeb http://www.programmableweb.com/api/spicynodes
- AASL. June 2011. Top 25 Websites for Teaching and Learning. http://www.ala.org/ala/mgrps/divs/aasl/guidelinesandstandards/bestlist/bestwebsitestop25.cfm
- edudemic.com, "The 35 Best Web 2.0 Classroom Tools Chosen By You" (August July 2010).
- Lyda Ellis, Andrea Falcone, "Techie Tools for Non-techie Types." Colorado Academic Library Summit 2010. Shelly Paul, "A Few New Tricks for Old Dogs"
- Tutorial from vivideinformatica, March 2010 (in Spanish); MEDT 6467 Spring 2011. Taught by Dr. Elizabeth Kirby Bennett. SpicyNodes tech tip instruction sheet: http://opc6467spring2011.wiki.westga.edu/file/view/6467_Tech%20Tip%20Spicynodes_spf.pdf
- Scot Gardner, "Spicy Nodes A Way To Visualize Online Information!" (October 2009).
- Examples of blog coverage in education-related blogs: Dianne Rees. "Spicynodes: mindmapping plus" (August 2010). Edna Sackson, "Spicynodes, a powerful mind-mapping tool" (August 2010). Lauren Kane, "SpicyNodes- an online mindmapping tool" (August 2010). Jil Wright, "Spicynodes for Mind Mapping / Course Mapping" (June 2010). Ms. H, a high school language arts teacher in Sheboygan County, "Nodes and Birds" (June 2010). Edutechnophobia Concept Maps and Timelines" (November 2009). Antonio Delgado Pérez, MA Ed, "Genera nodos de pensamiento con SpicyNodes" (In Spanish, August 2010). Kristen Swanson, "Spicy Nodes: My NEW Favorite Presentation Tool" (October 2009). John Goldsmith, "SPICYNODES: Free, Web Based Mind, Map Service" (October 2009).
- Embedding an interactive mindmap into your blog – SpicyNodes.org http://enhancingteaching.com/2012/03/28/embedding-an-interactive-mindmap-into-your-blog-spicynodes-org/
- Sally Garza, Lawrence School,"'Creative Presentation Tools" Presentation. (August 2010).
- Grundman, B. 'WikiNodes Brings A New Perspective To Knowledge' http://www.148apps.com/news/wikinodes-brings-perspective-knowledge/