dsfok is a simple and tiny application (just 76KB) that, despite its small size, lets you do a series of functions like make backups of any hard drive partitions.
dsfok also lets you create ISO images of CD-ROMs or DVD-ROMs, or create images of the content of diskettes. Those images can be later restored from this program.
dsfok also lets you encrypt and de-encrypt files, truncate long files, scan the PC volumes to get information, join two files together, etc.