GNU shar utilities
http://www.gnu.org/software/sharutils/

This is the set of GNU shar utilities.

shar makes shell archives out of many files, preparing them for
transmission by electronic mail services.  Use unshar to unpack shell
archives after reception.

uuencode prepares a file for transmission over an electronic channel
which ignores or otherwise mangles the eight bit (high order bit) of
bytes.	uudecode does the converse transformation.

remsync allows for remote synchronization of directory trees, using
e-mail.  This part of sharutils is still alpha.