1) All PCs should have a firewall and anti-virus software. Otherwise you are not only looking for trouble, you have just done the equivalent of punching the obnoxious neighborhood bully

2) If you have a wireless LAN, you should have encryption on, or you are transmitting your info across the neighborhood

3) only appliances that actually have some measure of 'intelligence' can actually respond to requests for information. The coffee pot will just be as dumb tomorrow as it is today.