I used to travel more over the past year. Goal was different places: England, Belgian. This means I also have to use untrusted wireless connection.
This leaves a good trace wherever you go. Simply by the fact that the MAC-Address being used every time you do a connection to any wlan. This is often stored, but How long? There are good example where this information is begin havest for money.
Beside, You never know who else listen and might want uses this data. To mitigate this problem I do following: I generate a random mac address for each new connection.
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