My brother got this from Thinkgeek.com and it was so cool that this year I bought it for all my agents. It's a great gift for kids too, once they're old enough to not be ant-eating morons. Instead of sand, the substrate is this clear gel. Best of all, the gel is also the ants' food and water source. It's 20 bucks, 30 if you want a light that goes underneath the farm.