The Lad Vampire was a freeware web-based application used by the Artists Against 419 to take some fraudulent websites offline. Using it was very easy: users simply started up the Lad Vampire webpage (see external links) and left it running.
The program worked by repeatedly downloading images and HTML files from the scam site until its bandwidth limit was exceeded and the site shut down. Many people used this program at the same time, and a fraudulent website was quickly taken offline. The rationale was as follows: if 50 people continuously downloaded a 20 kilobyte image simultaneously from the scam-site for 12 hours, this would use 40 gigabytes of site bandwidth. However, if the scam-site in question only had 10 Gb of bandwidth allocated to it per month, it would automatically shut down after a few hours. Afterwards, the web hosting company would either refuse to host the scam-site, or insist on charging the fraudsters a higher fee to do so. Even if the allocated bandwidth for the scamsite was subsequently raised from 10 Gb to 50 Gb, the AA419 team would simply target it again until it exceeded its allocation. In this way, AA419 supporters were able to have a real and measurable effect on fraudsters.
Note: AA419 stopped using the Lad Vampire and Muguito in September 2007. Neither is operational now.