Microsoft is giving away 5,000 gallons of gas as part of a promotion announced via e-mail. The details were sent out to limited recipients earlier today.

You have to work at a small business — defined as having between two and 100 employees — within the United States to enter. You can’t work for Microsoft or be a government employee.

If you fall into that group, you just have to fill out a quick form to enter. It has an option to opt out of spam lists, so there doesn’t seem to be any real catch to it. Microsoft says the winner will be announced around July 21.