VICE - Bring loops to life with the loop slicer plugin for Mac and Windows.
Frodo - Frodo is a robust Commodore 64 Emulator for the Macintosh.
C64 Forever - C64 Forever is a revolutionary Commodore 64 emulator, preservation and support package.
GameBase - bu22.com - the home of the GameBase frontend and databases.
JaC64 - A Java-based Commodore 64 emulator. Runs most of C64 games and many demos.
LMMS - Make music with a free, cross-platform tool