I've made the first change to help prevent spammers. Previously, people could add a Homepage to their profile. This was useful if you wanted to link to an informative website you ran, but obviously spammers were abusing this. So now the Homepage won't display on the user profile page.

I've also set up the forum so that I need to approve new users. We might still get some spammers as there are a lot of accounts that were set up but which don't have a single post. Some of these might be spammers. If these accounts start posting spam messages, I might mass-disable any account that hasn't posted.