Synth Alternative OS

There was a thread on Analog Heaven where someone suggested coming up with a list of alternative synth OS's. These are some of the suggestions and few that I've heard of. I'll update this post as I find more. Is there anything I missed?

Cheetah MS-6 - http://www.maad.net/ms6/firmware_index.html

Korg Poly-800 - Hawk-800 and AtomaHawk http://patrioticduo.tripod.com/hawk800/index.html

Rhodes Chroma - CC+ http://www.rhodeschroma.com/?id=cpuplus

Roland Jupiter-4 - Io http://www.roland-jupiter.org/viewtopic.php?t=414

Roland Jupiter-6 - Europa http://synthcom.com/Europa/productEuropa.html

Roland JX-3P - MIDI upgrade (not currently available) http://organix.inque.org/index.php?page=jx-3p-upgrade

Roland JX-10 - http://www.colinfraser.com/jx10/jx.htm

Roland MKS-30 - http://analog.no/cms/index.php?option=com_content&view=article&id=32&Itemid=41

Sequential Circuits Pro-One - Replacement CPU (under development) http://www.musictechnologiesgroup.com/

Yamaha DX7, DX7II - Grey Matter E! (no longer available) http://www.maths.abdn.ac.uk/~bensondj/html/dx7.html