Cat@log - Human-pet interaction
Ok, ok. This isn't strictly a phone - but it involves a twittering cat so we're having it. Cat@log is a not-exactly-convenient kitty collar which comes loaded with a camera, microphone, microSD card, accelerometer, Bluetooth and GPS.
The GPS hooks up to Google Maps to create a territory map, showing you where your cat goes when he's out and about, while the camera gives you a ride-along view. The accelerometer can also interpret certain actions like scratching, going up and down stairs, eating and jumping, all of which can be used to update a Twitter-feed - or even a full-on blog - of what your cat is up to all day long. Brilliant if you're particularly anxious about puss or away on holiday and want to check the cat-sitter is earning their keep.
There have been other cat-twitter-video-mash-up solutions, but this is the neatest we've seen yet. The adorable video (we recommend skipping the first minute or so) explains the features in more depth and even if you don't care about the technology, it features a bunch of cute cats - what more do you really want from an internet video?