A self-pouring teapot from 1886.
Apparently they were hugely popular. You raise the lid, put your finger over the hole in the top of the lid, lower the lid and presto, it pours.
One of the first patented Teasmades from 1902. Ask your granny if you have never heard of a Teasmade - they were all the rage in the 1960s/70s and, unbelievably, a modern "uniquely British icon" version is still being made.
One of my favourites - a combination lock stopper to stop your servants nicking your whisky.
This, and some other fine eccentric gadgets, are on hire to museums and other establishments from the delightful Maurice Collins mauricecollins@msn.com who puts all hire proceeds to disability charities. His own disabled daughter was the inspiration to start the charity Kith & Kids http://www.kithandkids.org.uk/ Heartwarming.