The fritzing project happens in a context of many other initiatives that empower designers and artists to work with computers and electronics.
It has become impossible to keep this list up to date or even complete. More overviews can be found on artsoftware.org and at the p2pfoundation (design category).
Controlling
Microcontroller kits for interacting with the physical world
Arduino (see also Arduino on Wikipedia for a long list of similar/compatible boards)
Wiring
Gainer
Phidgets
d-tools
MAKE Controller
DaKa
CREATE USB
Scratchboard
Manufacturing
Fabrication of shells and housings
Interfacing
Programming environments that can talk to Microcontrollers
Processing
PureData
Max/MSP/Jitter
vvvv
openFrameworks
EyesWeb
Scratch
Mobile
Programming for mobile devices