A couple of months ago I bought a weather station from Maplin, which is linked wirelessly to the display unit. This display unit is a touch screen and shows all the readings from the weather station, plus it also has a USB socket to connect to a computer.
The Python Software for USB Wireless WeatherStations is a superb collection of python scripts that works out of the box with my weather station. With a bit of tinkering on the Viglen MPC-L running Ubuntu 8.10, I have very quickly started outputting some very detailed graphs of the weather and tweeting data to @chris_house. I need to spend a bit of time to produce the exact graphs that I would like, but the default graphs shown here are pretty good for starters.