How can a PC read an external voltage?

I want to read the ambient air temperature and then store the results on a computer (cheaply, of course). I discovered that I can buy an LM34 integrated circuit temperature sensor for around $2.50. Its output voltage is a linear 10 mV per degree Fahrenheit, so at 75 degrees, for example, the output is 750 mV. How can I read this voltage with my computer, perhaps through the serial port, a USB port, or maybe even the microphone input or modem input ? I'm sure this is easier said than done. On the other hand, I am hoping there is some simple cheap way to do it. This is just an experimental application, so it doesn't have to be professional or foolproof, just something that works. Does anyone have any suggestions? Thanks in advance for any possibilities.

 

In my time it used to be done through serial port, but times have changed now & you don't even get a serial port in computers !

Google it.

 

thanks, Tony, for the engadget link. It's just what I want. I googled for a long time, but hadn't found it. Thanks again.