Simon Willison’s Weblog

Hash Collisions (The Poisoned Message Attack). Demonstrates the MD5 weakness by providing two deliberately engineered PostScript documents with the same MD5 hash but radically different rendered output. 4th April 2008, 7:24 pm

In rainbows. Dopplr generates a unique colour for each city using an MD5 hash. The colours are then used in subtle but intelligent ways throughout the design—right down to the favicon. 23rd October 2007, 10:39 pm