I thought I would share this because it is pretty awesome.
Yes it is actually possiable to play games on your android device (I should say MOST android devices) with a PS3 controller via bluetooth. This is achieved by using your ROOTED device and an app called "Sixaxxis controller", which i believe is 2 dollars on the android market. The free one they offer is for you to check that your device is actually compatable, so you dont have to purchase the app and find out later that it wont work. If you have a cable that will connect the ps3 controller to your android device, then you may not need the app at all.
The sixaxxis controller app will allow you to setup touch emulation profiles for your various android games (sonic cd, FF3, need for speed etc.) This means that you can control your android games, that are normally designed for the touchscreen, using only the ps3 controller. I dont want to get into how to do this, but there are tutorials that can be easily found with a quick google search. I mainly use mine for emulators. Every emulator on android I have ever used with a ps3 controller made it extremely easy to setup and get me going.
Now then, what I REALLY want to share is this. http://buy.thegameklip.com/
I have one of these for the Galaxy sII skyrocket and I can tell you its absolutly perfect. Its very sturdy and does exactly what its supposed to do. The downside is that it is not developed for ALL android devices, but rather a select few (almost entirely Samsung galaxy phones).
Hope ive brought something new to light for you. Playing my retro games on my android phone is really fun