I've wondered for a while why LMMS, the music/midi/sample sequencer, is so overshadowed by other audio editors like Ardour, etc. If you actually dig into LMMS, you can do some pretty amazing things in combination with a MIDI keyboard. Even without one, it's an awesome piece of software and pretty simple to start using.
And yet, there's no proper forum for the project and little documentation. How come? I think LMMS deserves better, and if it was more well-known, it'd be ranked as the best free package of its kind. It even has a Windows installer!