dd

This command will copy a file and perform a file conversion if specified.

Example:

dd if=/some/boot.img conv=lcase of=/dev/fd0 obs=16k

This command will write a boot image to a floppy disk in lower case letters. It will write at 16k at a time.

Options
if=file read from file instead of standard input
of=file writes to file instead of standard output
conv=lcase converts file to all lower case
conv=ucase converts file to all upper case
obs=bytes writes bytes at a time