Annoying buggers aren’t they?
I’ve administered several message boards and discussion forums in the past and sometimes you are limited to what your particular software can filter.
Looks like spambots such .ru, .br, .biz, there should be a denial of registration from certain domain extensions like these. At one point I did manual examination of new registrants which takes quite a long time if you have an active board.
“These advertisers remind me of some companies in the supplement industry” I like what you did there Marlan. Sometimes I tell people specifically about the idea answers part of the site and send many links to ideafit, so I hope it can be fixed. I like the fact I have to answer a math problem to post this response now.