Flwrap
From Just Solve the File Format Problem
flwrap by W1HKJ (David Freese) is a small desktop application that encapsulates a file within a set of identifier blocks. It is designed for amateur radio applications, but can be used anywhere the sending of binary files is restricted.
It first compresses the file with LZMA then converts to base-64 and breaks it into blocks with a 16 bit checksum.
