AVRminiProg -- compatible withprogrammers from Atmel
AVRminiProg is an integration of my previous-developed AVR programming tools, which emulate official USB-interfaced programmers from Atmel.
LPCUSBBoot implements a CDC over USB, and emulates a COM on PC. You can do ISP thru this COM port with MagicFlash or other compatible ISP tools. It is developped on GNUARM.
Versaloon -- Open source tools for embeded development
Versaloon can support OpenOCD to program or debug ARM
chips, that is O-Link.
Versaloon can support AVR chips as JTAGICE mkII or AVR Dragon.
AVR32, AVRXMega, PSoC support are to be added.