ZigBee sensors

I've been watching the space of low-power wireless networking for some time, as it has some cool possibilities for sensor networks. ZigBee is one such standard that seems to be gaining support. It's a lot simpler and lower power than other protocols like Bluetooth.

Make magazine had a really interesting article recently about using ZigBee inertial sensors to track the crashes and hits taken by a roller derby team, and use it to trigger "zap", "pow", "boom" sound effects. Very cool, and it all seemed quite simple!

I'd like to use the ZigBee temperature sensors in my garden. The long-term plan is to monitor the weather and supply tank water through an irrigation system only when it's needed.

So has anyone used this ZigBee stuff and know any good resources to start out?