You just don't want to do this anyway.
Who wants to send stuff between wifi networks and your laptop that you don't know about?
Here is true story:
Checked in at hotel to find a wifi site purporting to be from the hotel and looking all like the hotel "wifi service". Wanted credit card details to access wifi. In fact it was not, it was a hoax site designed to extract credit card info from hotel guests.
If you use free wifi without encryption you might as well write down all your passwords on a piece of paper and chuck em out the window.