At IBM, folklore divides the world into one-, two-, and three-banana problems. Other cultures have different hierarchies and may divide them more finely; at ICL, for example, five grapes (a bunch) equals a banana. Their upper limit for the in-house sysapes is said to be two bananas and three grapes (another source claims it's three bananas and one grape, but observes "However, this is subject to local variations, cosmic rays and ISO"). At a complication level any higher than that, one asks the manufacturers to send someone around to check things.
See also Infinite-Monkey Theorem.