This one's for all the tech-savvy cat owners out there. If you've had a problem with stray cats (or other critters) entering your home through your own cat's door, here is a possible solution.
The tweeting cat door makes use of functional and social technology to ensure that only approved felines can welcome themselves inside. An RFID reader is used to recognize the pet's collar tag and then the latch to the door opens. Optional features include a webcam and connecting the whole thing to Twitter—the creator of this particular device created funny messages (something like "Sadie is leaving to play poker with the crew") to document the whole thing and allow owners to stay apprised of their cat's whereabouts.
Here are the detailed instructions for how to make your own tweeting cat door. Have you hacked your way to being a better pet owner? Tell us how you use technology to geek out to help your pets!