So,... I'm just going to jump right to my thought, well I gotta set the stage a little.
Time Travel Topic (you know? My fav)
So most of the people who travel back re-invent stuff and become rich and famous and all that, so what about this for a story idea.
People who travel back to breed with primitive humans to make them smarter and more attractive.
Haha! Human and Klingon interspecies erotica!
Hahaha! I'm laughing too much at this...