We've never understood why some people refuse free money, but in the case of five million retirees and disabled veterans, that's exactly what's happened with the economic stimulus checks.

So here's one of our most important tax tips right now: If you are in one of these groups and earned at least $3000 in qualifying benefits, earned income or a combination of the two in 2007, you're entitled to the so-called tax rebate – even if you owed no taxes.

But to get your check, you must file a tax return before October 16.

Here's what you do: Get a copy of Form 1040A (click here to get it from the IRS web site) and write Stimulus Payment at the top of the page. Report any earned income on line 7. Social Security payments and/or veteran's benefits should be listed on line 14A.

Then, you must sign the form and mail it in. That's all it takes!

(To find out where to send you payment, click here to visit the IRS map. Click on the state you live in and you'll be given the proper address. You can also call 800-289-1040.)

Don't miss your chance at this free money!

Want to know what to do with your free money? Learn our top 6 suggestions for putting it to good and meaningful use. Also, be sure to check out more of our money-saving tax tips.