Pageflakes was an Ajax-based startpage or personal web portal similar to Netvibes, My Yahoo!, iGoogle, Wikpage and Microsoft Live that operated from 2005 until January 2012. The site was organized into tabs, each tab containing user-selected modules called Flakes. Each Flake varied in content; information such as RSS/Atom feeds, Calendar, Notes, Web search, weather forecast, del.icio.us bookmarks, Flickr photos, social networking tools like Facebook, YouTube, Twitter, email and user-created modules. Pageflakes had 250,000 Flakes and over 130,000 Pagecasts (publicly shared pages created by users with individual URLs).
Pageflakes was launched at the end of 2005. The site began in Germany, but was headquartered in San Francisco, United States. The company was initially privately funded. Balderton Capital (originally Benchmark Capital) invested an undisclosed amount in May 2006. Dan Cohen was appointed CEO in January 2007.  Pageflakes ceased operation in January 2012.
Drop Things An open source portal created by Omar AL Zabir (co-founder and CTO of Pageflakes) for a book he wrote on the subject.
Omar wrote a book "Building Web 2.0 Portal using ASP.NET 3.5" where he shows how to build such a portal that can withstand millions of hits. He talks about many performance, scalability and production challenges that are important for any high volume website. The book is available from O'Reilly and also at Amazon