don't see the value of the Sanguino?
Actually, the Sanguino kit is the same price as the Teensy++ and would be a better choice for applications that need two hardware TTL serial ports (without USB). It's a particularly good choice for hardware hackers - I have a project using the Sanguino circuit (an ATmega644P and a crystal) that was put together for $10 in parts.
That said, the Teensy++ is a good choice for the typical Arduino usage that uses USB connection to a computer.