With Portal 2's arrival, lemons replaced cake as the game's edible meme. (If you don't know what I'm talking about, read up here) So before this one is totally played out, let's acknowledge one of its more creative applications: these prop lemon hand grenades, by flickr user ammnra.
A creator of Portal-themed props, ammnra saw some fake lemons in a craft store "and couldn't resist." They're made of the plastic fruit; airsoft bb loaders forming the spoons; "random springs to make the spoons fly off when you pull the pins," and hacked chips from musical greeting cards that play Cave Johnson's lemon rant, followed by a boom.
Not for sale. (We think).
Combustible Lemons [by ammnra; Flickr. Via boing boing. H/T karnie]