You got to love the scene where the cop walks up to the window and wont listen to them and ask for the beer bottle and then takes a swig (EDIT). That was 1 of the funniest parts to me.
Another of my favorite scenes is when JC runs up to jetway & says "Don't worry - I'm a limo driver" before flying out the other end...makes me LOL every time I see it.
I love the scene where he whacks him in the back of the calf when they are going into the party or when they are frozen to the moped when riding into town.