Safe browsing from a wireless network is always risky, but even more so when you are in a public space that offers a wi-fi “hot spot”, like some coffee houses do.
If you are using wireless WiFi (802.11b) public hotspots then you are sending and receiving all of your traffic in “the clear”. It is penetrating walls, it is zooming across the street, and it is all readable plain text. Too many hotels have sniffable networks. Go to a conference with your competitors and you might be exchanging more than greetings.
This site offers a VPN service (for a small, monthly fee after free trial), available on just about every platform, that will protect your wi-fi connection from prying eyes…except maybe those looking over you shoulder.
Like any VPN, there was a bit of a performance hit, about 5 to 10% of normal traffic speed, but it was nothing that anyone will notice except on the slowest of 802.11b connections. Frankly, I’d take the security over the speed any day of the week.