Tether a Mac’s internet connection via USB
The Mac makes it easy to share its internet connection with any other device it is connected to. If you want the N900 to share a Mac’s Ethernet or Wifi internet connection over USB, this is what you need to do:
1. Connect the N900 to the Mac and select PC Suite Mode.
2. Setup USB Networking if you haven’t already. Make sure you can ping the N900 (192.168.2.15) from the Mac.
3. Setup Internet Sharing according to this Lifehacker post with one difference – select N900 (PC Suite Mode):
4. The N900 should now be able to access the internet.