YES you can. You need an IrDA receiver. MA620 works great. http://www.ma620.com/ The 8390 has an IrDA port on the side. Once the software is installed, activate the IR port on the phone and align it to the MA620. The PC will automatically find the Nokia 8390 as a wireless modem. You have to activate the data service for your cell plan. As I recall 8390 is a Cingular phone. Their Data plan is 3.99 a month and it uses your minutes. You can then use it to dail your own ISP. Last I check the connection speed is 9.6k I dont know if it's faster now. I doubt it. I uses to use the Nokia 8390 as my internet connection. It was too slow and counts against my minutes so I changed to Sprint Vision plan.
the 8390 is also an AT&T Wireless phone...