Craigslist
If you haven’t checked out Craigslist (many regional sites, including one for Austin), you should. It’s a phenomenal marketplace.
A lot of people use it for casual sex hookups, and hey, if I knew about that aspect of it back when I was single, who knows? But it’s also great for getting rid of stuff that has a little too much value to donate or throw out. I’ve posted several items for prices that are probably about 1/3rd to 1/5th what the item would cost new and gotten nibbles within a few hours, and sold the item within about a day. No fuss, no muss, and a lot easier than ebay. The posting process is dead-simple.
It’s got RSS feeds for each classified section, so if you want to tune in to, say, the new listings for old computers, you can do that. And it’s even got entertainment value in the hye-larious best of craigslist section