Springy

Springy is a simple to use, yet powerful archiving and compression utility for Mac OS X. Springy integrates seamlessly with the Finder and includes some very useful features. Springy supports all most widely used archiving and compression formats: ZIP, RAR, TAR, 7-ZIP, PAX, CPIO, CPGZ, GZIP, BZIP2, UNIX Compress, SIT, JAR, DMG and ISO disk images and some more.