One of my user needs to create a password protected folder in its pen drive. This is very simple but one more special requirement he asked for, if he insert that pen drive in any another pc he can able to see that folder over there without any software installation. This is quite tricky requirement. I found a tool for it i.e. Rohos Mini Drive. It’s a freeware with some limitations.
Rohos Mini Drive creates hidden and encrypted partition on the USB flash drive memory. You work with the files on the hidden partition without opening a special program. Those who have megabytes of sensitive files on the USB drive and seriously concerned with a data security, cannot imagine their USB stick without the hidden volume that is created using this tool.
Download the program from here. Install it and run it.
After installation the Rohos Mini Drive, insert your USB pen drive to the computer and run the Rohos Mini Drive application. Click on Setup USB Key
Insert a password.
It will create a partition namely K: with 297mb space. You can customize the partition size by clicking Change button.
Just you have to add file in this newly created partition, when you done just eject that partion as well as the pen drive.
For testing purpose you can insert this pen drive to any another PC. There it will show you one roho_mini_pendrive icon. Double click it and insert your password that’s it now you can access your password protected partition on that computer.
Source
My name is Vidyadhar Sarmalkar & I work as a consultant and have done RHCE & CCNA. 
No, it will not show any icon on any other PC. You would have to double click on Rohos mini.exe that is in your unprotected partition of your USB drive.
I Like Your post i found it very useful.All the useful information provided by you in this post
sounds very secure.Now a days data security is very important fact.For data security
USB Security has Become other important factor.
Great Work.
-Thanks for Posting.efender/