Howdy,
Do to a customer not ordering their broadband and phone provisioning until last minute (yay!), and an entire office move committed to, at a date prior to its install, i now have the joyous task of setting up without on premises internet!
3g dongle to the rescue i hear you cry, and that does work and pretty swiftly (albeit at a hefty price), but i do have another option - bt openzonewifi is pretty strong in the building already. but how best to access it via a 2850?
I optimistically tried a wifi dongle in the usb, that didn't work.
Couldn't find an option for using the routers wifi as the incoming wan interface.

My other thought is to use an old pc to connect to btopenzone and then share the connection and do it that way.

Any other thoughts?

I don't think you can use the wireless as a WAN interface, be interested to know if you do manage to do it though