I once got stopped by airport security because of the anode in my hand luggage (my hold bag was on the weight limit).

As the security droid looked doubtfully at this large lump of metal I launched into a comprehensive lecture about boats and electrolisis in a flat monotone till he glazed over and waved me through.

Carrying spare battens in a 6' length of 2" waste pipe caused a certain amount of consternation too.