Hot Swedish Action: For spelling ABBA on the game results screen
(+1 to anyone that knows who ABBA is)
Easiest way to get this achievement:
Play: 2 player Checkpoint battle (easiest if you have 2 turntables, but can also be done on-line)
Mix: Snow - Informer vs. The Jackson 5 - ABC
Difficulty - Any that you feel comfortable with and can do well on.
(I did this on Expert, My little brother did it on Medium)
*Will not work on Easy as there are no cross fades on Easy
Player 1 should do NOTHING at all for the first 2 checkpoints. Once the 2nd checkpoint has passed, play the rest of the song as well as possible, You should get an 'ABBA' rating at the end of the mix. And of course the achievement!
Player 2 really doesn't have to do anything. Have your girlfriend or wife try playing :)
I got this achievement first try using this method.