I picked up one of these "cat cubes" at Wal-Mart awhile back. Comes all folded up real small, held together with a band. Take the band off and it flies open, often hitting you in the face. One you unfold it and pop it open, you have a nylon cube with wirey metal edges providing some support. They come in blue-on-red, or red-on-blue. There's three sides with holes, the rest without. Inside are tassles hanging from one side, and there's velcro tabs around each hole - you get velcro strips also, and that's where the fun begins.
Moxie loved the first cubes so much I had to buy more. We're up to four now - at only $3.88 at Wal-Mart, and considering how much entertainment they've provided, I think I can TOTALLY justify getting, oh, maybe another one or two? ;-) Here I've got them in a 2x2 configuration, but you can change the layout quite a bit. I just wish you could go UP with them - that they were strong enough to add levels of height.
Moxie loves to hide in side, play-attacking the other cats as they walk by. Or she'll be inside, reach out and snag a toy, and drag it back in with her. (She must think she's either a ground spider or hermit crab?!)
But her most favorite game? Sit inside and then I toss a toy on top. I've got some videos of this game, but haven't uploaded any to YouTube yet. Here's some stills...
The toy goes on top:
Within secs it rockets into the air as she smacks it from underneath, sometimes staying on the cube (which starts the smacking all over again), and sometimes flying off (which means she might reach out and snag it).
Rinse and repeat.
I guess she can just see it's shadow, or perhaps the indentation - whatever, it's a blast! If you've got cats, these toys are SO very worth it!