So, how do you know if you're one of the lucky ones who will get a check? According to the official IRS site, "the vast majority of people who file a 2007 income tax return qualify, and many who don't regularly file a tax return may qualify as well. You're eligible if you have a valid Social Security Number (SSN), can't be claimed as a dependent on a tax return and have either an income tax liability or "qualifying income" of at least $3,000."

The IRS goes on to explain that the payments "phase out" among those who earned a certain level of income in 2007. For example, "the stimulus payment –– both the basic component and the additional funds for qualifying children –– begins to phase out for individuals with adjusted gross incomes (AGI) over $75,000 and married couples who file a joint return with AGI over $150,000."

The IRS offers a calculator (link below) that will help you figure out your own circumstances. If you are eligible, expect the payment to arrive in early May.
http://answers.yahoo.com/question/index?qid=20080325113046AAyyIE0