As posted in Nature:
"Taking a whiff of rose scent while learning a task and then being exposed to the same smell during sleep helps memories to set, researchers have found. The discovery could see students frantically spraying themselves with perfume before exams — although the effect is tricky to replicate at home."
I have to say that this totally cracks me up, because I used to sniff mint during exams when I was in college. I remember reading come study about military pilots having the scent of mint pumped into the cockpit because it increased alertness and helped them recall memories more readily: they were exposed to the smell during training, too.
So my plan was simple: I would sit at Perkins study and sniff an Altoids tin, and at my exam, I would do the same. Oh, what my professors must have thought of me.