Sony has done a great job at designing a flash drive without a cap; it also automatically retracts when withdrawn from a USB port. It's very thin and light weight; I can barely feel it hanging around my neck. This drive also works great with Vista's Ready Boost.
The only bad thing I have to say about this flash drive is that the price is higher than comparable flash drives and THE LIGHT IS NOT PURPLE!
The new 16GB Sony Micro Vault Click now offers everyone the storage capabilities they need to share thousands of photos and hours of video and music. With just one 'click', the hidden USB connector is revealed and ready for action no cap is needed to remove or misplace.