http://www.boston.com/ae/tv/snl25funniestmoments?pg=22
The link above is to Dan Aykroyd on SNL as Julia Child. Save the liver!
They have a list of a top 25 of SNL sketches. I'm still partial to the older stuff. There is even a great Eddie Murphy - Joe Piscopo duet as Stevie Wonder and Frank Sinatra.
Top 5
5 - Julia Child
4 - More Cowbell
3 - Patrick Swayze / Chris Farley Chippendales audition
2 - Mick Jagger
1 - D!ck in a Box
I'd have to put Chris Farley as the motivational speaker in any SNL top 5 list. Murphy's camera commercial with Steve Wonder was great too (the camera easy enough for Stevie Wonder to use it), also Wonder auditioning for a role as Stevie Wonder impersonator.
How about Will Ferrel's "Casual Friday" skit?
Lord and Lady Duchebag?
Can't argue with DIAB as the greatest ever though.