lzop is a file compressor similar to gzip. Its main advantages over gzip are much higher compression and decompression speed, at the cost of some compression ratio. lzop uses the LZO library for compression services.
In my g4l project I've found that lzop compression is about twice as fast as gzip with only a 10% increase in size. Plus it puts a much lower CPU load on systems. There is a newer version at lzop.org.