I mostly connect to my Linux distros to the  internet via a USB iPhone tethered connection (MyWi app). I have just installed an Windows XP guest OS via Virtualbox on Ubuntu 12.04.How do I connect the guest OS to the internet via my tethered iPhone connection?
How to share a tethered iPhone internet connection with VirtualBox guest?
networking;virtualbox
It depends on the network setup with your VM. If you just have a NAT connection everything should work out of the box. If you have a bridged connection you must change the bridge device from your existing network card to the new Ethernet device created for the USB tethering; most likely the device will be usb0.