sharing and internet connection via peer to peer

[debiani386]

hi everyone

i have 2 ubuntu computers hooked in via crossover cable and i have 1 
wireless cable.

What i want to do is temporarily set up internet connection sharing on 1 
computer so i dont have to swap my wireless between my 2 computers.

ive googled and gone through several tutorials with no avail. even tried 
internet connection sharing via firestarter and it didnt work


is it possible to set up internet connection sharing with a p2p network 
like this  and of so, how?

--cj