lzop
- Real-time file compression. Features list, documentation, and download.
- http://www.lzop.org/

ZLIBC
- Zlibc allows applications to transparently access compressed files. As soon as the application attempts to open a compressed file, zlibc uncompresses the data on the fly. No kernel patch, no recompilation of the executables nor the libraries i
- http://zlibc.linux.lu/