I've been researching advergaming because I'm so bored. I ran across this--they consider it a 'classic'. It IS addictive for a while--the Dyson vacuum cleaner telescope game.
I got up to level 25 without too much difficulty, but then stayed at 25 for several hours before I figured it out. One of those driving down the road "AHA!" moments. And then after it's so freakin' easy you decide you must be even stupider than you imagined for not getting it earlier.