ETA: The 10-20% percent is the down payment you make. For example I want to put 200 worth of clothes on layaway at sears; I pay 1.00 for their fee plus 20 dollars down, the day I put it in. I then owe 180 dollars which is divided into 4 equal, bi-weekly payments, over 2 months. Sears only makes a dollar in addition to the 200 one would pay with cash or credit card. Its not 10-20 in addition to the amount of the purchase, so I am not paying 220 dollars for 200 worth of clothes. Sorry if that confused people. It's not a racket, if you tend to use cc to pay for things,but do not pay your bill off in full every month, it saves you money b/c you don't pay interest or finance charges as you would with a c.c. If you are able to at any given moment to buy, it prob would not benefit you.
I love layaway! I started doing it about a year ago, in an attempt to get rid of my credit cards and I'm hooked :P Anyway Sears, Kmart, Burlington have it year round. You pay a small fee, usually a dollar, and a percentage of your total, ranges from 10-20% depending on the store, then make bi-weekly payment til its paid off! Sears and Kmart will refund your money, after its paid off, if you change your mind. Burlington will only issue store credit. There isn't any interest, finance charges or anything like that, so its worth it. Make sure you plan in advance for how long it takes to get it out, they give you 2 months. You can always pay it off early, no penalties.
Check with smaller stores as well, a lot of them offer it.
Good Luck!!!