MSPDebug is a free debugger for use with MSP430 MCUs. It supports
FET430UIF, eZ430, RF2500 and Olimex MSP-JTAG-TINY programmers. It can be
used as a proxy for gdb or as an independent debugger with support for
programming, disassembly and reverse engineering.

WWW: http://mspdebug.sourceforge.net/