I've been battling with spammers on this forum for years, but I just did something that dropped my spam forum accounts by 95% overnight. Hopefully most people already do this, and I'm just a moron for taking this long to figure it out. However, if someone else is having a hard time blocking forum spam, my suggestion is this: Go into your forum software and find the section that allows you to ban certain email addresses from signing up. Look to see if you have a "wildcard" option that you can use to block groups of email addresses (for example, if * is your wildcard, blocking *@gmail.com would block anyone from signing up with a Gmail account). Block the following email addresses (I've used * as my wildcard- replace * with whatever character your forum software uses as a wildcard): You'll still get some spam accounts and find additional email addresses to ban, but blocking this list will make a huge dent in your spam flow.