I'm developing a shoutbox for my site and have got the basics for it working. I've pretty much solved most problems with word-wrapping and alignment. I need to know what other safety precautions I should implement to protect from malicious users. Thanks for any input.
URLS:
*site is not near completion*
http://viciousdesign.intoxia.com/phptest/ << main site
http://viciousdesign.intoxia.com/phptest/shoutbox.php << shoutbox (if you wish to test anything you think might mess it up)