...."Seinfeld" Season 5 episode "The Wife" features one of my favorite Jerry-centered storylines of the entire series: Jerry and his girlfriend (played by Courtney Cox in a pre-"Friends" era) pretend that they are married so that they can both get a discount on dry-cleaning. Naturally, as their pretend marriage progresses, they show all the signs of a failing married couple. Really funny stuff here.
George and Elaine's connected storyline is less-than-great: a man Elaine is interested in but who is showing conflicting signs of reciprocating affection catches George peeing in the shower. This storyline is pretty funny and is indicative of the envelope-pushing nature of the series but does not give much of a payoff in the end. But Kramer's storyline saves the rest of the episode as he cannot get a good night's sleep (which provides Michael Richards plenty of material for hilarious physical Kramer stunts) and overdoes things in the tanning bed before meeting his African American girlfriend's parents.