Using his previous experience on his Atmel based BusNinja, [J]oby came up with the Launchpad SPI Explorer. The serial parser is based off his previously covered RPN Calculator. If you ever want to debug any SPI based device or sensors, you can talk to it using the Launchpad without writing any code. The interactive shell allows you to send SPI packets serially with the Launchpad acting as a gateway.
Controlling a Microchip MCP23S17 SPI 16-bit I/O expander:
[ b111:4 0x20 10:2 r:64 ]
Which translates to:
Write 7 7 7 7
Write 10 10
Read 64 bytes
More on his Launchpad SPI Explorer here. Debug away!