I'm currently playing with writting a today plugin which displays the current weather plus 5-day forecast.,
I too wanted something simple. I did not want all the extras that the others provide. Just weather.
It basically works. It obtains its weather feed from the MSNBC website (
http://www.msnbc.com/m/chnk/d/weathe...?acid=UKXX0260 - where the last bit is the city's code)
When it is a bit tider, can send you the cab files (and source if you so wish...)
Adrian