The TU-40 is just a bit underpowered for emulation, although it would handle stuff for the most part. I need to see how much it would sell for these days...
I found some more stuff on the linuxdevices site (appears to be a good reference), including this Atom MB at what was $80 in January (2008) which includes the Atom 230 CPU which was $29 if purchased alone:http://www.linuxdevices.com/news/NS6489450984.html
It had a whopping 8 USB along with stuff I don't need though, but it looks cool.
Also the Icop eBox-4300 looks neat (as a system) and that article refers to some more devices that might be of interest:http://www.linuxdevices.com/articles/AT4708024578.html