I know it's possible to tether iphones to use their internet connection on the computer, but can it be used the other way? I want to use the computer's network connection on my Ipod Touch through the usb cable. Is it possible? Thank you!
Not exactly but you can use the computer's ethernet internet connection via Wifi to the iPhone.
In that case just go to System Preferences > Sharing, then
If you are using a pc with windows you can follow the instructions reported here. Basically: