I have a Drinkwell and the furkids love it. I bought the only size reservoir that was available a few years back. (The one mentioned at the SpencerTheLion website above.) Recently they came out with a reservoir that is double the size. Not sure if I'll upgrade soon or not, but probably will one sometime...

I did forget and leave it running one time over a long weekend when we were all away. The cats went with me, so I didn't think there would be a problem but forgot about evaporation. The motor burnt out and the cats were VERY disappointed. Replacement motors are cheap, at least, and easy to replace in the Drinkwell.

Good luck!
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Oh, recently they've come out with cat toys on mini-fishing line with reels: we have two -- one with an irridecent (sp?) fish and one with a furry mouse. I'm getting rather decent with how to hold my thumb on the reel so they go the length of the room, then I twist them while winding them in. Livvy likes it, Cassy LOVES the challenge. Do you think your furkids would like this toy?