I was using kneeling some, when I was having the coccyx problems. It would work for a bit, then I'd start having nerves go to sleep and such. And that was back when we had the computers in the other arrangement, so I could sorta kneel and use it, even if it did give me a crick in my neck.

Now, getting in and out of kneeling uses the muscles that were cut open, so isn't too comfy - also, doing it in the living room, if I did have the computers back in the old alignment, would get my back and tush run into by active small children a lot.