Fast file scan

[Shawn Shealy]

>In article <299 at lysator.liu.se> pen at lysator.liu.se (Peter Eriksson) writes:
>>I`d like to know how to scan all files in a directory (and it's sub-
>>directories) for a specific string (without regular expressions) as fast
>>as possible with standard Unix tools and/or some special programs.

My favorite is:

find <Directory_Name> -type f -print | xargs fgrep "<Search_String>"

but I would not dare say that it is "as fast as possible".