|All you have to do is change the wifi access/secirity-key (frequently incorrectly referred to as the password).|
Change to something "you" can remember; and perhaps email it to yourself (and save the email in a saves folder). Also perhaps stick a note on the base of your router - highly unlikely your neighbour is going to be to see it?
Perhaps use part of your Soc Security number and some other characters?
Also even change the SSID for your router; again making a note of it as above.
message edited by trvlr