VIDEO: '30 Rock' finale preview, Kenneth Parcell's got a famous cousin

The funniest comedy on network television is closing out its third season this week.

The clip below has some guest stars, which is cool -- Best part of that? Clay Aiken is apparently Kenneth's cousin -- But it's the series regulars and the writing for them that usually knocks "30 Rock" episodes out of the park, so I'm really hoping -- since this is the last Donaghy/Lemon fix we'll get for a while -- that Thursday's finale is one for the TV history books...