I've been using Twitter for a few months now (see Twitter: Three Benefits to Bloggers). It's a quick way to promote blog content, and it allows me to write quick updates that I wouldn't want to do a whole blog entry for.
It was pretty cool when people started following me. But I've realized some "followers" are just spammers in disguise. They'll set up a profile, put an entry with some kind of spammy website (sometimes a porn site), and then start following whoever they find. I guess the idea is to get me to visit the site, as well as others who may check out my followers. Needless to say, I'm now having to check every profile that follows me and make sure it isn't Twitter spam. I don't want my Twitter account to have questionable profiles on it. Just another way spammers make our lives miserable.