Get two quarters from a soda machine using a dollar and smaller change

Pop quiz, hotshot

You are in a launderette^* just before closing on a Sunday night. You have a sopping wet load of laundry sitting in the dryer. The dryer works 15 minutes for 25 cents. It will take you at least 30 minutes to dry your clothes. Just to make it interesting, let's say one of your laundry items is a shirt for your significant other which absolutely, positively has to be ready for him/her first thing in the morning.

The machine takes only quarters; you only have a dollar bill and some smaller (non-quarter) coins. The change machine is broken and the attendant, who doesn't speak any languages in common with you, doesn't have any quarters either. Your only hope is a soda/pop machine which vends cans for $0.60.

What do you do? What DO you do?

Good job, sport! You make sure to put a dime or two nickels into the machine first before inserting the dollar. Only then will you attain the sought-after pair of quarters.

Trust me, it won't work if you put the dollar in first. That mistake cost me some flowers, dinner and free rides in my car around town for a week.

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^* the generic word for the trademark name Laundromat.

some_guy hasn't had much luck with this method; his machines return the excess change immediately after inserting the dollar. The trick still works for machines around me. Maybe I have the Fonzie touch.

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Addendum 9 March 2006: The same trick works if you want two 100 Yen coins from a beer machine selling 500 ml cans of Kirin for ¥350 and you have a ¥500 coin and a ¥50 coin.

Additionally, if you're nice, some soda machines will let you get your change back if you opt out of a purchase. You can sometimes insert a dollar bill into the Giver of Life, and then proceed to press the "return change" button and be rewarded with 4 shiny quarter-dollar pieces clunking their way out of the change return slot.

This can be a bit of a gamble, however, as some machines will be nasty and refuse change after devouring your bill. It's up to you to decide which machines are the kind ones and which ones are pure evil.

It is worth noting that unlike the vending machines of yore, most modern drink machines do not simply return your own change back to you. If you have fifty cents worth of small change, it can easily be converted to two quarters simply by feeding the machine and hitting the coin return button.