Twittad: All your backgrounds are belongs to us.

So many people are twittering now, people use it to stay in touch with their friends - like me - and people use it to promote their websites new posts - like adland does. Not to mention using it to hit on Salvator Romano and all the other Mad Men out there. ;)

So, self-promotion and website promotion is already there, clearly - but how about using it as a place to advertise? That's exactly what Twitterad suggests, they'll sell you peoples background image on their twitter homepage. You can sell your background to the highest bidder - and for the ad-buyer the minimum buy is only .99 cents.
Under Quality control they write:

TwittAd 's technology will continually check to make sure that a Twitter user is serving the ad. Every hour the ad is served, the Twitter user will receive money in their TwittAd account. Once the TwittAd users account reaches $20 they can request payment. If Twitter user removes the image before the advertiser's time has expired, we alert the advertiser and they have the option to give negative feedback to the Twitter user. Advertiser will receive credit back from TwittAd for the time their ad was not served.

There are a few obvious problems to this idea, for one - how often do you look at anyones elses twitter page? Tweets are showing up in IM and text messages on phones, and on your own page. Then, the background images aren't clickable - so where do you go once you've seen the ad? I guess those who like to do general branding all over the web might like the idea, but I don't see twitter users in mass selling out their space anytime soon. Also, twitter themselves - who don't have enough funds to afford texting the European and Australian users anymore - don't make a dime off this idea. "No, TwittAd is not affiliated with Twitter.com. TwittAd was built using the Twitter open API." Call me when I can help Twitters revenue by selling my background image, until then, no thanks.