Jimmy Fallon is classic.  He was always laughing in Saturday Night Live skits.
Yeah Jimmy Fallon is a great comedian, and a surprisingly good actor too!
I love the cowbell sketch.  That and the Debbie Downer sketch about Disney World.  They always make me laugh.
Debbie Downer
Debbie Downer is a name of a fictional "Saturday Night Live" character who debuted in 2004, and who was loosely based on notable Quebec personality, "Chrissy Downer" and portrayed by Rachel Dratch.
The character's name, Debbie Downer, is a slang phrase which refers to someone who frequently adds bad news and negative feelings to a gathering, thus bringing down the mood of everyone around them. Dratch's character would usually appear at social gatherings and interrupt the conversation to voice negative opinions and pronouncements
screeching along with a bagpipe with castmate Jennifer Aniston sitting on the couch beside her and clearly trying to keep from laughing. The "Saturday Night Live" sketches featuring Debbie Downer (Rachel Dratch) are also notable for corpsing. Jimmy Fallon is also known for breaking character by laughing on "Saturday Night Live." Perhaps the most famous examples of this are the appearances of Bill Hader as the "City Correspondent" Stefon on SNL's "Weekend Update". The jokes were often rewritten between dress rehearsal and broadcast, so