Search an entire drive for character string

[David G. Miller (aka DaveAtFraud)]

fergus at bonhard.uklinux.net wrote:

>Is there a way (dunno, maybe using dd and grep?) that an entire drive,
>and not just the files on it, can be scanned for a character string?
>Fergus
>
There is (was?) a hex editor for linux called bev that might do the 
trick.  The problem with using dd and grep (e.g., dd if=/dev/hda | grep 
'string') is the best you will get is that the string you're interested 
in is somewhere on the disk. 

Cheers,
Dave