The The Secret Armory of General Knoxx Add-on for Borderlands has 10 achievements.
Reached Level 61
Reached Level 51
Killed each of the loot midgets
Completed all missions in Secret Armory
Killed Crawmerax the Invincible
Destroyed the Lance Depot
Paid for a worthless tour of the world's largest bullet
Rescued Athena
Destroyed a Lancer while in a Racer
Built the New Car: Monster