Mine like the squirrel dude as well. It's much less noisey and more portable than the old buster cube I have. I use it quite often in hotel rooms to distract Zoni when traveling.
Zoni is a chewer and likes the newer Nylabones which are more funky shaped than the traditional ones. They both love the dental dinosaurs. Nemo never chews on any nylabone or similar things but he will chew on the little dinosaurs.
Zoni likes the little squeaky tennis balls, and she will play fetch with them.
Otherwise, one of their favorites is a cat toy which is basically a little battery powered squeaky mouse hanging from a stick that squeaks when you move it. It's not very sturdy but it they absolutely love it. It only cost a few dollars.
The other toy is a plush "tree stump" with little squirrels inside which the dogs can pull out thru several different holes. It's a lot of fun too. Once they pull them out, I just stuff them back in again. Here's a little video to illustrate. They love flinging the little squirrels around. I put a little duck in there too which makes the noise.
http://www.youtube.com/watch?v=PNR_23a5ezk