We have this set of mini Caterpillar construction equipment that both of my kids adore. We put it to good use a few days ago when it was raining outside. I filled a cookie sheet with 1-inch sides with dry rice, added the front loaders, steamrollers, dump trucks, etc. and my 3-year-old daughter went crazy. She played for over an hour dumping and digging. In fact, we left it on the table, and she's played with it every day since. Quick, easy, inexpensive, and hours of entertainment? Yes, please!
*By the way, I've gotten lots of comments recently about the amount of mess that things like this create. Yes, they absolutely can be a disaster. And I think some kids handle these types of things way more calmly than others. But we include clean-up as part of our process (my 3-year-old has a set of brooms, dust pans, etc.), and we go over the rules beforehand. We don't ever intentionally spill the rice/sand/beans, etc., and we always clean up our messes. If anything is ever thrown, dumped intentionally, or mistreated in any way, it is put away immediately, no questions asked. And, if there is resistance during clean-up, it goes in time-out, and we don't get it back out that day at all. But, just a little note, I make sure it's put in an area out of reach but not out of sight. I want the action to pack a punch. So, definitely use your judgment with your little ones. You may need to wait until they're older to tackle this. But I definitely wanted to dispell any assumption that I don't have a giant mess to clean up after these types of things. I've just accepted that as part of the fun. Proceed at your own risk! =)