This is something that happens to me on a regular basis. It's like snorting when something funny catches you off guard. But more often than not I'll be eating cereal. Those most memorable times this happened are:
With my sister, coco pops and Russel Howard.
Listening to Innuendo Bingo and eating Bran Flakes.
Watching 'Midnight Love Snack' and eating porridge.
Midnight Love Snack was recommended by someone in the cast with me in The Wedding Singer - he's a guy with some funny videos. Made me laugh anyway.