The ever-increasing capacity of USB flash drives lets you bring along not only your files but also the applications that open them. Windows Vista makes it easy to set programs on USB thumb drives to run automatically when you insert the drive: Put the program you want to run in the device's root directory, and create a two-line autorun.inf file (see below for instructions) that points to the program. With the drive inserted, check Always do this for software and games, and select the Run This Program option. From now on, that program will run whenever you insert the drive.
Though the autorun feature of the U3 USB standard in XP is enticing, you can't edit the U3 autorun.inf file for your own purposes. Some U3 hacks exist, but you needn't bother with them, thanks to the great little Autorun USB utility. To use Autorun USB, install it on your PC, insert your thumb drive, right-click the drive's entry in Explorer, select Properties, and click the Autoplay tab. From the drop-down menu, select each content type that you want to place on the drive, check Select an action to perform, and click Autorun USB Drive from the list of options. Once configured, Autorun USB works like a charm. Unlike other tools I've tried, it runs only when the media is properly inserted--and it disables the Windows 'What should I do with this drive?' query.
To work, Autorun USB must find an 'autorun.inf' file in the root directory of your thumb drive. Open Notepad and type the two lines below in an otherwise blank document: [autorun]
Change the name of the executable file at the end of the second line (unless you want Microsoft Word to open automatically, in which case you can leave the text as it is). Finally, save the file to the thumb drive's root directory with the name autorun.inf.
Note: Though autorun.inf works with Windows XP, Vista's security may cause it to fail, so use Vista's built-in autorun function (described above) instead.
Encrypt a USB drive by switching to NTFS
By default, Windows allows you to format USB thumb drives to use only the FAT file system. But formatting the drive as NTFS rather than FAT lets you encrypt folders and access other NTFS file-management features. To reformat a flash drive as NTFS, right-click the drive's icon in Explorer, choose Properties, click the Hardware tab, select the drive from the list, choose Properties again, select the Policies tab, and check Optimize for Performance. NTFS will now appear as an option in the drive format dialog box. After reformatting, repeat the process, but this time select Optimize for Quick Removal so you don't have to deal with the Safe Hardware Removal dialog box to avoid losing cached writes when you remove the device.
Caveat: NTFS isn't designed to work with removable media, so after selecting the Quick Removal option, you might lose data if you remove the drive too soon after writing data to it.