Option 1 is to use WPA and use radius for authentication rather than a pre shared key. This means each person has their own keys so they cannot use the preshared key to capture your traffic and decode it... it is not actually as simple as just having the preshared key though. Not simple to setup and you need a radius server and for best security you need a certificate server.
Option 2 is to use a router that can have multiple SSID. Then you would setup different preshared keys for each. In effect each person would have their own network.
If you are worried about a direct attack on your computer from one of these machines you need to insure you are running a firewall since you will not have a router and the NAT to protect you from many common attacks.