My birds' favorite boxes are old covered kitty litterboxes (well-scrubbed, believe me). They will stand in line with their legs crossed waiting to use one. But these things are ten to fifteen years old. I've looked at litterboxes on the market currently, and eeyuk, they just aren't the same! If I want more of these I am going to have to go to garage sales, or put up one of the weirdest want ads Craigslist has ever seen.