On my 24th birthday, I wanted to do something even more special than the Michael Jordan sticker, so I designed one of Kobe Bryant that was dye-cut into the Laker's shape. I made it all in Photoshop and then saved it as a PNG with that white outline around it.
These ones were really popular amongst my friends and were gone fast. I have the one in the photo above on the back of my laptop and people still ask me where to get it.
I either used Sticker Mule or Sticker Robot to print it. I can't remember.