Wireless hacking

So, my cable went out today, and I noticed that since the last time I was forced to go wireless, my neighbor installed a Linksys router. Here's the fun bit: it's unsecured. IS it possible to view the files on his computer, etc? What can I do?

Sure; use smb to probe his share settings to see if there's anything interesting out in the open. Otherwise, use a modified rcp client to dictionary attack his login.

Also, if your card supports rfmonitor mode, then you can sniff out any login/passwords he uses, and maybe use those to get it.