Song slips are often used for notepads around places that are very busy with single people. Phone numbers, URLs, all of that are put onto your slips and distributed by singers and non-singers alike. You never know when the slip finds it's way into someone's hands.
Knightshow: If you get a PDF printer for your PC you can print to a PDF file and carry that into Kinko's on a thumb drive for printing. They just charge me the printing and binding cost and I save the wear and tear on my printer at home. Just a thought so you don't have to replace that toner all that often