fencepost

As the person with the write-protected drive listing that Arthur linked to, I'm going to suggest checking into customizing a U3-capable drive. There are some (possibly-dated) instructions here: Looking for a USB Flash Drive with Read Only or Write Protect Switch, and you can find more information by searching on "custom U3" or "customize U3". U3 drives present with two partitions, one as a virtual CD-ROM with software and a second that's writable.