I'll tell you one "fringe" product I installed on my desktop computer just
this week - it's that
Mozilla Firefox browser.
Wow! what a difference. Yes, there are a few issues, like even some scripts on PPCA.com don't show up properly, but the Tabbed browsing, speed and custom options made me change it over to my "default" browser.
It is going to be difficult for Linux to make similar inroads because of like you say all the software is built for Windows/windows mobile. But if people start adopting it on a wider scale and it's easier to get and install - like Firefox was for me (took all of about 5 minutes - it's a 6 MB install) then Linux will see their day.