Most cat owners will realize that cats are “very” hard to keep track of. What I mean is that your cat probably likes to hang out by himself/herself in the neighborhood and comes home for meals and whatnot.
Of course, not everyone has the luxury of living in a house (including me), but for those of you who do, you might just be able to benefit from making one of the cool Twitter Cat Door that will “tweet” whenever your cat uses the cat doo