I use it mainly for firmware updates (as a secondary controller). That way I don't have to include/exclude the device or change drivers. Makes updates real simple.
For Zigbee I have three XBees (kit of 3 with carrier boards + Xbees is $99). Good for repeaters and for investigating the network (have to connect one of the Xbees to a computer to scan the network--can be freestanding to act as repeaters).
