I do not do a lot of product promotions, but this Logic Analyser from Dangerous Prototypes is so sweet! It is such a simple hardware design, pulled together with some great programming and serial ram overclocking. For $30USD you get an 8 channel, 256k sample, 60 Mhz(!!! - overclocked) logic analyser that supports the SUMP logic analyzer protocol and thus can use the Logic Sniffer (An alternative OLS client), another great open source product.
This item is on my list now for future debugging of my bare-metal ARM designs.
So check it out yourself:
Product page: http://dangerousprototypes.com/docs/Logic_Pirate
Available from Seeed @ http://www.seeedstudio.com/depot/Logic-Pirate-p-1750.html
Client Software: Logic Sniffer (An alternative OLS client)