A Dallas Semiconductor 1-Wire bus would be much more useful and versatile. You can string quite a few devices off it so you can have multiple temperature sensors. There is a whole range of bits, last time I played about with it there were memory chips, addressable switches, clocks and temperature sensors.

A PIC chip could be used to interface the bus to the serial port or you can buy a serial port adapter.

I've got an iButton developer kit which is their 1-Wire stuff in a small metal can and it is quite neat. You could use an iButton to authenticate yourself to the empeg if you wanted.

- Trevor