The best idea I've seen related to WiFi is the VPN service. Regardless of what security you have on your own laptop, when you hook into a "public" hotspot you really have no way of knowing how secure that particular server is. By using the hotspot server to send only encrypted transmissions, you get back to essentially the same security you have at your home PC. Of course it is another fee to pay, and some software to install - and another service provider to train.
Note that this is just an "unbiased observer" comment, since I haven't attempted to actually use any of this stuff.