I know a few of my fellow Buxrarians have inquired previously about other means to make a few bucks online and I found these sites not too long ago. They pay you to send out sponsored tweets.
Each site has it's own rules, requirements, etc so make sure you read them.
Some of these sites want you to have an already established twitter account - meaning you cannot create a new account that is used solely for sponsored tweets. You have to be using it for other tweets as well.
1. Sponsored Tweets - http://sponsoredtweets.com/
2. Magpie - http://members.be-a-magpie.com/twitterer
3. Ad.ly - http://ad.ly/
4. My Likes - http://mylikes.com/