In my case, I had been running Ubuntu(now Debian) on my desktop for over a year before finding Nokia's tablet series. I was looking for a replacement for my (Rockboxed)Iriver H320 that was -better-.
I looked around and the best I could find(cheaply) was a Archos 605 Wifi. I got it expecting to be able to hack it and run stuff on it... and was -sorely- disappointed. Literally two days later, I ran across Nokia's tablets(which I saw as far superior), found a N770 for $10+s&h on ebay with a "battery problem", got it home, charged it and it worked perfectly.
I was extremely happy with that, aside from the fact that video playing was sub-par at best, and a 8GB SD card had to be soldered in. Oh well.

A couple months later, when I had some money, I found a N900 on ebay for $325 used, bought it, and have loved it ever since - I like the browser, using x-term for all sorts of things, and the ability to leave it on all night for instant-internet functionality.