Combine a whistle and a data storage device into a small, pocketable gadget that you can take with your anywhere you go, wearing it around your neck. The PNY Whistle Attache USB Flash Drive is a fully functional (unhygienic) whistle that also lets you store digital information.
The device comes in 8GB, 16GB and 32GB versions, starting at $20. I have to recommend it to remain your personal USB flash drive. Find it at Brando.