I saw a poster for Snakes on a Plane this weekend and it reminded me of me cracking myself up and wishing Jason had been there to appreciate it.
When I was flying to NC for my last trip (Jason followed one day later), I was de-flipflopping myself in preparation for my cozy socks that I always put on for long plane trips and I thought how funny it would be if Jason was sitting next to me because I would have reached down into my bag and pulled out the socks violently and said "Oh my God! Socks on a plane!".
It occured again later when I decided it was time for my snack as I would have again reached down into my bag to retrieve my packet of mini Pringles and then grasped them a few inches from my face (you know, as if I was holding a snake's neck away from me) and said, "Arrgghhh! Snacks on a plane!". I doubted my neighbor in seat 12B would have appreciated this as much as Jason would have. Because, you know, to know me is to love me or some crap like that...
So, to sum up, pretty much anything starting with a "s" sound and ending with a "k" sound will work here. Feel free to substitute your own s and k sound words and crack up those around you. Just be sure you actually know the person around you.