PDA with barcode reader recommendations?

[Peter Dobratz]

Can anyone recommend a PDA with the following features?:
- built in barcode reader.  Needs to read standard retail barcodes
(such as those found on a six-pack of beer).  A PDA with barcode
attachment would work, but no dongles.
- connects to linux using USB or some other standard interface, and
doesn't require a kernel recompile (using stock Ubuntu 7.10 x86)
- can run custom applications.  Python and wxWindows would be sweet,
but anything that can be developed on linux would be fine.
- hobbyist price, sub $500.

Does such a device exist?

Thanks,
Peter