Searchable database of markets for fiction, nonfiction, and poetry. Includes a submission tracker. Subscription-based, with a free trial period.
The Submission Grinder
Searchable database of fiction markets (nonfiction and poetry coming soon). Similar in many ways to Duotrope (including the submission tracker), but all features are available free.
Ralan’s SpecFic and Humor Webstravaganza
Website of market listings primarily focused on science fiction, fantasy, and horror.
Aswiebe’s Market List
Free email- and spreadsheet-based market updates for science fiction, fantasy, and horror.