I think a single-click button "Spammer" should allow committers to lock an account and hide all messages and files that he sent, but that still requires somebody to implement it.
I'd expect that to be pretty effective -- like graffiti artists, spammers want their work to be seen, and a site that quickly removes them will not be worth the effort for them.
Unfortunately, the spammers are using automated tools to locate, register on and post to victim sites. The tools are distributed (running on compromised PCs) and massively parallel, so they really don't care that some of their posts are never seen. I'm reluctant to mention the name of one particular tool I'm aware of, but as well as the above, it also has OCR to defeat CAPTCHA, and automatically creates throw-away e-mail accounts with a range of free web-mail providers for registration purposes. -- Andrew McNamara, Senior Developer, Object Craft http://www.object-craft.com.au/