Data can be trivially intercepted even if you are connected using cables,
after the WiFi device you're connected. Even if you are 100% sure your WiFi
connection as perfectly encrypted, you should never rely on this to provide
you even a bit of secure and private communication!
On another note, it's much better to keep your WiFi unencrypted and share the
connection, so other people can use it. This provides freedom from cell
phones, and independence and privacy for people in general. You aren't really
using you Internet most of time, probably less than a 1% of time even.
I'm told that in some countries it's illegal to share free WiFi access, which
is an injustice. So be aware. Maybe a weak encryption can provided instead,
to circumvent such laws. Maybe those laws aren't really enforced in practice
or the penalty isn't severe. In Bulgaria there are many places which offer
free WiFi access, so it seems pretty safe.
