I see there are a few Acer WT-300 thin clients for sale cheap on eBay at the moment. I've tried Google, but I haven't found any information one way or the other regarding installing Linux on one of these machines.

Has anybody had any experience with Linux on the Acer WT-300?

http://support.acer.com/network/html/wt300_specs.html

Based on the specs there, even if you could shoe-horn it in, I don't think it's gonna do a lot

Those specs aren't completely unreasonable (for hardware power) for a thin client (depending on how thin you mean); however there is nothing in those specs that suggest its bios supports, eg, pxe-boot. And you would need pxe-boot or a similar system if you are to do something other than execute its buit-in WinCe stuff.

This isn't 'installing linux on it', of course; its using it as a thin client with a linux host; maybe you mean 'reflashing' the system to use linux as a stand alone OS'; that would be harder, but might still work (but it would still be a thin client).

Of course, it might support something similar to pxe-boot and they may just have missed it out from the spec. More Googling for you!