How to get a PS3 controller working on Ubuntu?

How to get a PS3 controller working on Ubuntu?
I want to use my PS3 controller as a joystick for playing ROMs. How can I get it working?

i didn't use Ubuntu window,i bought laptop that already installed Ubuntu,i reinstalled windows 7 on it.

yep dear serch it in google i will try myself also that

Here are some instructions directly from the Ubuntu community site. Always nice to get the info from the Ubuntu website itself.