What do I spend a silly amount of money on? How might I scratch my own itch?

To explore business opportunities, I didn’t do in-depth market research; I started with my credit card statement and asked myself, “What do I spend a silly amount of money on?” Where did I spend a disproportionate amount of my income? Where was I price insensitive? The answer was sports supplements. At the time, I was making less than $40K a year and spending $500 or more per month on supplements. It was insane, but dozens of my male friends were equally overboard. I already knew which ads got me to buy, which stores and websites I used to purchase goods, which bulletin boards I frequented, and all the rest. Could I create a product that would scratch my own itch? What was I currently cobbling together (I had enough science background to be dangerous) that I couldn’t conveniently find at retail? The result was a cognitive enhancer called BrainQUICKEN.