7-Zip

• • Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
  • Unpacking only: ARJ, CAB, CHM, CPIO, DEB, DMG, HFS, ISO, LZH, LZMA, MSI, NSIS, RAR, RPM, UDF, WIM, XAR and Z.
• For ZIP and GZIP formats, 7-Zip provides a compression ratio that is 2-10 % better than the ratio provided by PKZip and WinZip
• 

The main features of 7-Zip

• High compression ratio in new 7z format with LZMA compression
• Supported formats:
  • Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
  • Unpacking only: ARJ, CAB, CHM, CPIO, DEB, DMG, HFS, ISO, LZH, LZMA, MSI, NSIS, RAR, RPM, UDF, WIM, XAR and Z.
• For ZIP and GZIP formats, 7-Zip provides a compression ratio that is 2-10 % better than the ratio provided by PKZip and WinZip
• Strong AES-256 encryption in 7z and ZIP formats
• Self-extracting capability for 7z format
• Integration with Windows Shell
• Powerful File Manager
• Powerful command line version
• Plugin for FAR Manager
• Localizations for 74 languages

7-Zip works in Windows 7 / Vista / XP / 2008 / 2003 / 2000 / NT / ME / 98. There is a port of the command line version to Linux/Unix.

On 7-Zip's Source Forge Page you can find a forum, bug reports, and feature request systems

Download 7-Zip for Windows:

7-Zip 4.65 2009-02-03	Type	Windows	Description
Download	.exe	32-bit	7-Zip
Download	.msi
Download		x64
Download		IA-64
Download	.zip	32-bit	7-Zip Command Line Version
Download	.tar.bz2	Any	7-Zip Source code
Download	.7z	32-bit	7z Library, SFXs for installers, Plugin for FAR Manager
Download	.tar.bz2	Any	LZMA SDK (C, C++, C#, Java)