Granulate is a program for splitting files in place. The program
serves a purpose similar to the standard UNIX split, but differs in
one important way. For split to operate on a 40MB file, you must have
more than 40MB of free space on the disk. On the other hand,
granulate only needs one chunk of free space on the hard drive, where
a chunk is the requested size for the output files.

WWW: http://exe2bin.com/granulate/