From the South Park episode "You're Getting Old".
Stashed in: gifs
Source and discussion of Kyle and Cartman's friendship:
The System That All Creative Geniuses Use To Develop Their Ideas
Evolved carbohydrate digestion and obesity strongly linked
How To Propagation: Regrow Mint from Cuttings
Dear algebra, please stop asking us to find your X. She's never coming back and don't ask Y.