snicker = 1,480,000 hits
snigger = 409,000 hits
Dictionaries treat "snigger" as a secondary spelling of "snicker." I was just curious how secondary it was. It's more popular than I would have guessed.
(To control for the candy bar, the actual search terms were "snicker -snickers" and "snigger -sniggers. [Who knew that I would ever find occasion to use the term "control for the candy bar"?])