Somewhat up to date (2015):
Project that reverse enginered the memory controller put on each WonderSwan Card.
- Flashmasta - WonderSwan Color Flashcard
Flavor is trying to do an WSC Flashcard. ZOMFG UPDATE He did it! The WS Flashcard is available!
- Oswan for opendingux
Since Cygne and its successor O-Swan never had been made open source this got my attention. It is a leak? Code piracy? I jet have to find out.
- Liranuna's DualSwan
WSC Emulator made for the NintendoDS. He made this emu from scatch and I think thats why it worths a look.
- Cygne - A wonderswan color emulator
Dox old homepage. One of the past grandmasters when it comes to WSC emulation.