All I can say is ‘Wow’
I read this today on a local news site and the only thought that went through my head was "wow"... Essentially a malicious individual hacked the Epilepsy Foundation's website and posted hundreds of rapidly flashing images. While I don't condone it... I can understand why people think they should target websites for profit or pride... but this? It's just plain mean... It makes me wonder what the world is coming to.
Update: Apparently this is old news and I'm a little slow finding out about it.

Honestly, I didn't chuckle… I don't have anyone close to me affected by it, but I think it's pretty sick… There's nothing funny about it… It's sad and mean and disgusting.
Ok, while pretty vicious, I just want to ask…did you chuckle at all about it? Come on….
Just once? It doesn't count if you have epilepsy or someone you know closely does, in which case, my apologies.
I've heard of this a long time ago, but not as defacements or hacking or anything, but rather forum trolls posting such things on places like epilesy forums.
Then again, I used to know websites that had those damned "intro" flashes of color. As if THAT was ever a good idea…