The Lenna (or Lena) picture is one of the most widely used standard test images used for compression algorithms.'lena' or 'lenna' is a digitized Playboy centerfold, from November 1972. (Lenna is the spelling in Playboy, Lena is the Swedish spelling of the name.) Lena Soderberg (ne Sjööblom)
a free, portable, extendable, high-performance executable packer for several different executable formats. It achieves an excellent compression ratio and offers very fast decompression. Your executables suffer no memory overhead or other drawbacks
audio compression format designed for speech. The Speex Project aims to lower the barrier of entry for voice applications by providing a free alternative to expensive proprietary speech codecs. Moreover, Speex is well-adapted to Internet applications and
The Portable Network Graphics (PNG) is a format for storing compressed raster graphics. The compression engine is based on the Deflate method [RFC1951], designed by PKWare and originally used in PKZIP.
a tool that simplifies the process of compressing and sending your files online. It isn't a replacement for the traditional desktop compression tools, but its just a tool that makes things easier by cutting down all the 'krunching' hassles.