WinZip Open Source alternative

If you ever needed an alternative tool for WinZip or WinRar, try 7-Zip.

• High compression ratio in new 7z format with LZMA compression
• Supported formats:
  • Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
  • Unpacking only: RAR, CAB, ISO, ARJ, LZH, CHM, MSI, WIM, Z, CPIO, RPM, DEB and NSIS
• 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

http://www.7-zip.org/download.html