Hmm..
If you can, ask them first. Tell them that you won't be doing any illegal things (people are paranoid that ALL WiFi users are just using their point to traffic things like kiddie porn and P2P), and ask nicely. Bring a plate of cookies.
IMO, it's not stealing if you don't have to crack it to get on.
I leave mine open on purpose, so if someone is in my neighborhood, needs google, drives by my house really fast to look it up, I'm cool with that. WiFi should be available to everyone. The internet has become a medium for news, entertainment, communication, bla bla bla.
it's NOT ok to crack into it. For example, I have 2 wireless signals available to me: My own (left open) and neighbor (WEP) Now, if I sat outside their home (or.. on my bed, I can get to it from there!) and cracked the password, THAT would be bad because they put a lock on it, basically saying "don't get on here."
So.. uhh.. ask your neighbor.
