Two suggestions...
First, if you make sure the drive is Mac formatted then most folks will have a problem opening it (assuming they're trying to do it on a PC).
Second, you can create a disk image that's password protected. To do this open Disk Utility, click on New Image. Set the size to custom, and set it to a little below the available space on your thumb drive. Set encryption to 128, and make the format a Sparse image (it'll grow as needed). Click create, and you'll be prompted for a password.
When done, copy the ".sparseimage" file to your thumb drive. The image at this point will be small (something like 50MB), but as you add stuff it'll get larger.
Thanks for the info Chris.
One thing I don't understand about this strategy is what happens when I drag a 3.5GIG "Documents" folder to the flash drive (inside the sparse folder)? Does it encrypt the whole folder as it transfers it? Would this take a gigantic long time?
I would like to use the flash drive as backup and convenience of always having all my data in my pocket with my pocketchange.
To access a file would I have to un-encrypt the whole 3.5 GIGs or just the individual file???
Thanks,
Jeff