Get a bunch of tiny Nassarius snails. They are great fun to watch (they look like little slimy swans gliding around through your sand) and they burrow in and out of the sand quite a bit.
I was just whining that all the seeming sandsifting critters had huge downsides (from cucumbers that wipe out entire tanks, to starfish that eat themselves to death, to urchins knocking things over and getting stuck, etc.) I managed to find 4 of these guys, and while that's nowhere near enough for my 55gal, they were great additions, and still really the only macro critters than play in my sand/cc.