http://www.securityfocus.com/archive/1/385340/2004-12-18/2004-12-24/0
http://secunia.com/advisories/13645/
I would recommend AGAINST clicking this if you're on Windows, but --> http://www.milw0rm.com/sploits/KERNELBLUE.ani
That's pretty amazing that an animated cursor can cause a Kernel crash :)
Fun! :)