The idea of having a full-fledged distribution ona Zaurus sounds tempting, but ... it really doesn't work out. While having a stock install on a PDA may be pretty geeky, it's usability is very badly.
Stock distributions don't care about resource constraints, they don't know about touchscreens, display brightness, rotation, size, 64MB memory, 400 MHz speed etc. etc. etc.
Unless you just want to show off and don't want to actually work with your device, you can attempt to use a full fledged stock distro, but trust me - it isn't fun - not even for us geeks.