You can start pretweeting by using the app from http://pretweeting.com/ . When you register for pretweeting you will get $5,000 for buying words. You can buy  50, 100, 500, or 1000 slots with each slot equaling one word. price of each word will be calculate based on the current popularity of the word. For example if a word costs $10 then it will be mentioned in one percent of all recent tweets.

Listen  the introduction of pretweeting.com.

“Make a (virtual) profit by buying and selling words on twitter. Predict what’s going to be hot and buy it up before it hits twitter, and you’ll make a killing once people start talking about it. (no actual money required!) “.