Alien/Aliens reference in the Waste of Space DLC.
If starting the game from scratch you will initially need to raise about $5000 to open up the Museum. There is one egg up there that is separate from the main batch.
Other than that from the Crowd Kicker headquarters/start head out and to the right. You will reach a large clutch of eggs spread out across this area. Proceed to burst all of them, they do not necessarily need to be headbutts. Once the last egg pops so will the achievement. There are 37 eggs altogether, 36 in the nest and 1 in the Museum.
Just a quick note this needs to be done in one sitting, although as shown it only takes 4-5 minutes. If you pop some eggs and then quit out the eggs will be back the next time you play.