Benedikt Sauter have been working on on USBprog – an open source multipurpose tool which supports AVRISP MKII, ARM7/ARM9 programming, JTAG debugging, simple USB to RS232 conversion or 5 line I/O.
This is interesting concept as you don’t need to worry about adapter firmware. You just need to connect to online firmware pool and update adapters firmware. As project is completely open source you can download schematics and USBprog base firmware and build adapter by yourself, or you can grab preassembled adapter jus for 22 Eur. Works on Windows, Linux and other operation systems.
