It looks like the ADV3500PC is taking a beating here and it's (mostly) well deserved.
However, I still like mine and find that it works well for many tasks.
I use the ADV3500PC to run FBReader and Mobipocket Reader, Foxit Reader, VLC Media Player, Internet Explorer (with Flash), Microsoft Office 2000, etc.
I've bought three things to improve usability:
1) A plate stand for < $5 to keep the unit vertical so the intake fan doesn't get blocked;
2) A mini-folding USB laptop notebook cooling fan pad like this $8 one (
http://www.eforcity.com/pothmnnbfan1.html) to keep the unit well cooled while in its upright position;
3) A Solidtek ASK-3462 Bluetooth Keyboard to help with text and mouse input. The Solidtek keyboard has a built-in touch pad that addresses the recurring screen calibration problem (mine is in the lower right corner) but a USB mouse would do just as well.
Of course, these additions don't solve built-in drawbacks like ADV3500PC's 256MB RAM but they turn it into a useful and comfortable road companion.