Have your ever found yourself running short on ice packs during baseball, swimming and those picnic times of the year? You can make your own ice packs using a zipper sealed bag filled halfway with water. Adding in two cups of alcohol the mixture won't totally freeze and will be great for those scrapes and bumps where a hard ice pack won't work well.
If you want an ice pack for indoors you can use a hot water bottle instead of the zipper bags.