I owned a Wii for about 48 hours... we bought one, thinking that it would be a hit at the Thanksgiving dinner we hosted at our place, but we just couldn't get into it. I really admire Nintendo's ability to innovate, and maybe in a few months the Wii will fill out its potential, but for now I'd rather have an XBox 360 or PS3. Luckily I was able to sell it on eBay for a small profit.
On the flipside of eBay experiences, I had a horrible time selling my old laptop. No need to get into the details here, but in the end I got negative feedback that I didn't deserve. I learned some valuable lessons, though:
1. Don't get into potentially hairy negotiations with people (a) fresh off a large cup of high-octane coffee, and (b) without taking the proper time to think the issue through.
2. As cold and impersonal as it may look, it's really not a bad idea to include some legal-ese in your eBay auction to cover your ass.