I’m not sure whether the AirPort Express is totally cool or just sort of mildly interesting. For the most part, $130 is too much for the use I’d expect to be able to get: I imagine I’d use it to turn a wired connection into a wireless one in situations where I’m a guest somewhere: someone else’s house or a hotel. Neither seems very likely. Those friends to whose houses I’d bring a laptop probably have 802.11, and at a hotel I’m probably fine with an ethernet cable. Most hotels I’ve been to don’t have reasonable internet, anyway.
The stereo thing looks neat, but… I don’t really have a stereo.
I’m sure there’s a market for the thing, but I’m not sure who’s in it.