We’ve just released a new exiting service. Instead of a regular banner exchange (like to one we have at exchange.xaviermedia.com) it’s an exchange where you exchange tweets with other Twitter users.
When you for example post tweets for another user in your Twitter time line you earn credits. These credits can then be used to buy tweets on other users time lines. This gives you much much more exposure to what you have to say. For example if you’re starting to market a new product or service this will let you reach out to new markets for free.
Since you always have to approve the ads you want posted in your own time line you can make sure only relevant ads are posted.
Twitt.US also got a referral program where you earn 10% of the credits your referrals earn. So why not test the services provided by Twitt.US and write a review about it with your referral link 
