Looking for a thermometer to connect to a PC

My officemate and I were talking about this this morning.  We'd like to be able to use a PC to measure the temperature outside.  Ideally this would be a serial connected device with a probe that could easily be placed outside.  Google found us some, but there seem to be very complex and cost around $100!  We want something much simpler, anybody know where we could find such a device?