It's so nice to know that there are equally odd people out there 
We do Mr Creosote 'fuck off I'm full' and 'wafer thin mint?'
A lot of Father Ted.
An awful lot of film quoting, when he's waffling on I'll say 'Be quiet now sir, there's a good gentleman' (Zulu), or if something missing / empty we do '...and no cello..' from The Ladykillers.
Cold hands up the back, duvet popper races, imaginary prizes for the best burps / farts, pinch punch battles.
If we're planning the day, it always has to include a trip to the executions..'if I want any of my little friends executed that is'.
We play Banana Car, and have to punch one another when spotted.
A lot of exaggerated accents. Talking to each other in Clanger-ese. Or Pingu-ese. Occasionally pirate.
When asked what's for dinner, he gets told 'a smacked arse, a poke in the eye, or a bunch of fives...' he usually chooses smacked arse.
If there's a cat on a lap, it's fully acknowledged that the sat on person is fully incapacitated, even if it's 'black cat, not our cat'.
At bedtime, we don't turn off the light, we turn on the dark.
Much making up of songs, changing song lyrics, spontaneous singing based on a single word uttered.
And probably loads of other things that are just so normal to us now that they don't seem odd...