I started an Open Salon blog in late 2009. You can read my latest post on home health aide training and aging parents.
So why have a blog on Salon.com? First of all, I'm not special - anyone can open one. Most important - the page rank is anywhere from 4 to 7 (depending on who rates it) and the links are DoFollow. Second, if you pop your AdSense in, you get one block of advertising. I think I've made a dollar there :-)
I don't post complete junk, or just links - I used to post updates on my $10K/month experiment, but I'd rather just blog on interesting topics related to my other articles now. The eldercare crisis blog post is a perfect example of that.
I also write at Blissfully Domestic to get high-quality backlinks (and, like Open Salon, you get one block of advertising with your AdSense account). Same with HubPages and Associated Content. Even if the site has NoFollow links, using the anchor text to target my exact keyword phrase can help boost an article's ranking - just not as much as a juicy high-PR DoFollow.