Just a quick post to mention two markets. The first is The Devil's Food horror anthology, thought up by the fine people who bring you The Monsters Next Door. The editors are looking for supernatural horror stories in which humans are treated as food for some kind of monster. See the guidelines for full details, but stories should be between between 3000 and 7500 words, and according to Ralan they don't want reprints. (Simultaneous submissions are okay, though.) Deadline for the anthology is April 1, 2009, and payment is $25 plus one contributor's copy.
The other market is not a paying market, but sounds kind of neat anyway. Micro100 is in the fledgeling stages and looking to put together monthly issues of short horror stories (max 250 words) for free online perusal. Originally, the guidelines stated a maximum word count of 100, which I thought was more exciting (and went with the name of the website better) but I guess they think it will be hard to get a lot of good stories that short. They also mention something about poems, and say they will respond to subs within a week. See the guidelines here to submit, but the only payment is exposure. If you're okay with that, go ahead and send them something.