Living in the UK where Seinfeld isn't very well known, I have been inserting dialogue from the shows into my conversations and passing it off as my own. For example:
'Serenity now, insanity later' ( slipped this in when someone was talking about Buddhism)
'I think you know my policy'
'I practically raised his kids' ( disappointed with the response - I think it's a classic Kramer line - maybe it was my delivery)
Reference to 'Jimmy legs' ( got a BIG laugh out of this which is strange since taken out of context I would have thought it was meaningless)