Filing US federal taxes under Linux

You aren't supposed to be able to, as the ATO application for filing Tax returns on line is in fact a Windows application written in VB6 (I used to work with the blokes that wrote it), but it's so old now that it runs perfectly well on Linux under WINE.

The Dutch tax office (belastingdienst) have been providing their electronic tax forms for Windows, MaxOSX and Linux for a couple of years now. The Linux package is built using autopackage and works flawlessly on any distribution I tried.

The Polish tax office provided a program to file taxes via Internet, and it was involved in a GPL violation (of SSL library used), security flaws, anticompetitive behaviour (it's, of course, Windows-only and closed) and thwarting reverse-engineering attempts (named after Janosik - who was our local version of Robin Hood). Finally, AFAIR, some of it was opened a bit (freedom folk want only the protocol specs), but I didn't track it that much...

California uses PDF's with forms, and a modicum of sanity checks (are all required fields non-empty?). As I recall, you can enter data using Acrobat Reader and then submit it electronically.