My husband showed me these videos way back when we were dating. They're done up like serious videos but their information's quite amusing. I'm posting the Sushi video here. I love the salt lick joke. :)
They're done by a Japanese comedy duo called Rahmens, consisting of Jin Katagiri and Kentaro Kobayashi.
Some others in the series are: Chopsticks, Apologizing, Ocha (green tea) and Origami. Check out youtube for more by them.