It will get spent; you don't think they're going to put it in a Savings Bond to earn interest do you?

They borrowed X number of dollars and they'll spend that much. They're hoping we'll individually spend the money and our "demand" for goods and services will create more money-making enterprises here at home which will help the economy or that at least everyone will "feel good" about the whole thing which will make us less anxious and more apt to spend our money, etc. However, Mr. Bush just made a speech a day or two ago acknowledging the average American is going to spend it on needs like the higher oil and food prices and that can't help much.
But your $600-$1200 versus the $1.36? billion borrowed is like swimming upstream; won't even pay 1 minute's interest on the loan? And it's not like the Government is going to notice or send you a thank-you card?

There's nothing in it for anyone in sending it back? Nice, responsible "gesture" but can't get the salmon upstream because there's a dam in the way and no fish elevator? Spend it the best way you can see to help someone if you don't want it for yourself because you feel it's irresponsibly putting future generations in further debt. Help a kid in a future generation, like notthemama suggests with charity?