What they want:

Tor.com welcomes original speculative fiction short stories and poetry. We define “speculative fiction” broadly, including SF, fantasy, horror, alternate history, and related genres.

Length: Up to 12,000 words
Payment: 25 cents a word for the first 5,000 words, 15 cents a word for the next 5,000, and 10 cents a word after that.
Submission Guidelines: http://www.tor.com/page/submissions-guidelines