[Growster...]

Yes we use a 'legs' one, Ma'am, usually to open the opposite end of a tin of corned beef, to push it all through!

By far the simplest opener is an army one, which would come with cases of rations!

http://www.themilitariashop.co.uk/1981-dated-british-army-tin-opener-same-as-wwii/

It is such a simple piece of kit, I wonder why you can't just get them free with every copy of the Radio Times!