JägerMonkey is the code name of Firefox 4's (and later) JavaScript engine (glad I know how to type umlauts). The name is a reference to a well-known beverage (who would have thought). JägerMonkey also has this awesome sticker (and t-shirt) design, though the science-savvy are fast to point out that this is not a monkey but an ape in the picture. Pssshhh, don't mention it to anyone.