MacBreadboard

[Info-Mac]

Download: http://archive.info-mac.org/sci/macbreadboard.hqx

MacBreadboard is a Digital Electronics Breadboarding Simulator.
It has a very unique interface in which you "move" chips & wires on a virtual breadboard. MacBreadboard and WinBreadboard (the PC version) are used in many colleges and universities around the world. It's ideal for prototyping designs on the computer before going into the lab, or in situations where using actual breadboards is not practical for some reason.
The Full product includes 78 simulated TTL chips and it can even display timing diagrams.

--Eric Conger