Here's a neat idea. This "Online Coat Rack" by Blair Ross would help you figure out what you need to wear when it comes to the coats, scarves and umbrellas waiting for you at the rack. The barometer is presented in an attractive analog fashion to boot.
At the same time, it's this analog display that really limits the information that the Online Coat Rack has to give you. It takes up quite a bit of space, leaving out other useful data such as temperature. With an LCD screen it could do even more, though maybe at that point you may as well be at your computer.
Check out another view of the Online Coat Rack down below.