Very nice multi-thread file splitter and joiner. It splits files of any type and size (larger than 4GB), selecting parts by size or parts number. Does not need to be installed. This program can even perform CRC32 file integrity checking, filename and date/time restoration.
32 and 64 bit executable is available.
This application is really portable, so it does not requires installation, just download and run. It has an internal multi-thread engine that provides a really fast operation, including files larger than 4GB.