Best ever?
Hmm...
Runners and riders for me:
1 - The Office Comic Relief episode. Others have said similar, with good reason.
2 - I'm Alan Partridge, the stalker episode. Another well-loved classic, though there are probably three from that first series that I'd rank in my top ten.
3 - Phoenix Nights Alternative Comedy Night episode. "I want my money back!" "I wanna moonwalk, son. Life's a sh**ter." Pure class.
4 - Early Doors Big Boy's Beano. A superb end to a pretty much flawless series.
5 - Human Remains episode 3 "All Over My Glasses." Funny and bleak, my kinda stuff "You can't put gays in a shed, they like the darkness." Top stuff.
As soon as I list this, I'll probably think of about seven more.
The winner for me? Close, but I'll have to go with The Office. Brent's dance still makes me cry with laughter, and I've seen it far too often.