I'm in the market for a sand table but don't like the offerings at the stores so far. Late last night I found this DIY version and I'm committed to making one in the next couple of weeks.
The parents over at Life with Two Little Vikings had the great idea of using PVC pipe to make the structure for the sand table. If you want to make one for your kids, you'll need twenty feet of 1.5 inch PVC, some "elbows", some "tees", PVC glue, a concrete mixing tub, and sand. You can read more instructions over at their blog.
Image: Life with Two Little Vikings