Proprietary software I use and actively endorse:
Reaper – http://www.reaper.fm/
Renoise – http://www.renoise.com/
Reason – http://www.propellerheads.se/products/reason/
Live – http://www.ableton.com/live-8
Native Instruments piano/synth/epiano/hammond modules – http://www.native-instruments.com/#/en/products/?category=44
Many many other effects and instruments.