I *love* this idea. Why haven't I ever thought of it myself? I once learned that our brains are effective processors but not great at retaining information. I can't tell you how many times during the course of a day I think "I should tell my mom about that movie," or "Remember to ask about the party the next time you talk to Bob," and then what do I do the moment I get off the phone with my mom or Bob? I say, "Darn it, I forgot to mention the movie or ask about the party!"
This notecard idea is so easy. The next trip to the grocery store will definitely include a saunter down the office supplies aisle.