well its not a real hack, but people putting redirects into the shoutbox to throw up some flash page or such... any way to turn off redirects or malicous html from running in it?

Whenever someone posts on shoutbox their IP is logged. If you find a post that is malitious you could ban that IP and delete that shout. There is a ban IP somewhere for nuke you can use. (not sure where). That's all I know to do at this time.

Make sure you add command such as embed or swf to your censor list, that should take out some of the redirects.

Mayby you can think of some more commands to block.