Many home routers now feature VPN capabilities. Windows server editions have VPN capabilites as does most *nixes. You can also use VNC although it's a little slow, and tightVNC is IIRC free for windows. I also think that you can use an XP feature (remote assistance, I think it's called), but I don't have XP and have never tried it.
My new years resolution is 1280 x 1024