Run a lost-and-found desk for imaginary thoughts

A harmless thought I keep losing is [THOUGHT], or use 'a small idea' if I prefer privacy. Create a fictional lost-and-found desk with three absurd candidate items, one claim-ticket question, and a final item that resembles the thought without pretending to recover an actual memory. Include a practical one-line capture method I can choose to use next time. Keep the exchange under four turns and offer a skip option. Check that no invented item is described as something I truly said or did.