Everybody loves a good Time Waster. Everybody loves ninjas. And everyone loves solving mathematical equations, right? Number Ninjas is all this goodness rolled up into one slick little Flash game!

You play the number one, armed with a ninja's favorite projectiles: throwing stars. And by "stars" I mean +, -, /, and *. To complete a level, you've got to defeat enemy numerals using the correct operator to satisfy the equation in the bottom right corner.

Sure, nailing this eight with a + would do the trick, but who knows what other numbers lurk around the next corner? Perhaps there's a two waiting to pounce? Who knows how many other nasties this guy brought to the fight. Getting the correct mix may take you a few tries on some levels, but I didn't find the process frustrating.

If you want a good way to keep your brain limber for a few minutes, Number Ninjas is a good way to do it.

[via JayIsGames]