Caring for litters of puppies, we were burning through the wee wee pads. I found this economical and environmentally friendly alternative...human bed liners. I buy the multi packs so that I always have some clean ones. They launder beautifully. I also find these MUCH easier than the grass doggy patches which are not fun to wash. These are the ones we recommend to encourage them for potty area. The others below are good for crate and playpen lining, under food bowls and to protect car seats.
NOTE: Some people swear by the grass patches for puppies, but I have found them to be not fun to clean. I much prefer these.