When The Bomb Goes Off
This collection of platformer microgames depicts the last 5 seconds before nuclear armageddon. Each level is a little 5 second puzzle where you have to figure out what to do and execute. This game was sponsored by Addicting Games and was played millions of times!
This game was originally released in Flash and can't be played in a browser nowadays. You can play it on Newgrounds if you install their plugin: