I use
phpbay on a blog, it's a pretty nice plugin. I use it to setup a memorabilia page, and it's quite easy to blend auctions in with your content post/or pages, and there is a feature to mask the ebay urls for the auctions and the auctions pictures the urls end up being yourdomain.com/auction.php
Earnings wise I have only been using the plugin a little while so the earnings haven't been much.
I'm buddies with the plugins author real nice guy, goes out of his way to help his users.