I thought about doing something like this ( I know it's being done by many right now)...
Set up a "PPC Search engine" where every result is a CPC affiliate link.
Get a bunch of domains and set up LPs that point to the main search script.
Sell for a price that is just low enough to cover listing, domain reg, etc. costs. The more you sell, the more inbound links you have, but more importantly, the more people you have looking at the auction, checking the site and clicking the paid links.
If you price them right, and make your terms clear so they don't come back crying about a refund, then you are essentially getting free exposure.
Another twist to this would be to use a reseller account or dedicated server to set up a "Web Host" that charges, say, $9.99 per month. It's your server, so you can provide as many or as little features as you want.
In the auctions you could say:
" the first month of hosting is free, but after this month, it is $9.99. The site is hosted by [insert your "Web Host" here] and after you win the auction, I'll send you a link where you can log in and add your payment details."
You just effectively forced your service onto another unsuspecting "customer". You may think this is a bit unscrupulous, but it is no different from the tactics used by other small companies, such as AT&T, Microsoft, Wal-Mart.
The thing about the hosting, though, is that most people who buy into this probably don't know a whole lot about the "internets" and are not gonna care where it's hosted.
The downside to this is that if you are running the host, even if you have CPanel, you may get a lot of support mails that ask you things like "if I mail you some pictures, can you put them on my site?" and "someone told me my site is not getting hits. can you put some hits on my site?"
Not a bad plan, if you accept and understand the crap that comes with it. But doesn't everything these days come with a certain amount of crap?