Whenever I talk or write about my own security setup, the one thing that surprises people -- and attracts the most criticism -- is the fact that I run an open wireless network at home. There's no password. There's no encryption. Anyone with wireless capability who can see my network can use it to access the internet.
To me, it's basic politeness. Providing internet access to guests is kind of like providing heat and electricity, or a hot cup of tea.
I don't have a DHCP server running, so anyone who wants to use my wireless needs to configure a static address on the correct subnet. I'm happy to do this for guests who don't know how, but drive-bys are strictly on the do-it-yourself system.
I figure both my local network (the wired and the wireless parts) and the various machines are as secure as I need them to be. Traffic is encrypted from the browser or via my vpn, and machines are locked down with firewalls. If I'd use my machine at the local watering hole, I see no reason to suspect that it's less safe at home. As for my neighbors using my bandwidth, I hope they'll return the favor if my router craps out.
IT Blogwatch: Leech my wi-fi? No way! (and messy rack)