Sand Substitute?

[backafter30]

I'm wanting to get some of my snakes out of their tubs and into some nice display cages that attempt to replicate a natural environment for them. I've got most details figured out except what to use as a substrate in a desert environment for some southwestern kings and rat snakes. Sand seems to have a bad reputation, but what would give the appearance of sand (or reasonably close) without the impaction issues? Thanks!