If you're on a Mac, you should really consider getting the complete Stuffit package. It not only enables you to stuff and unstuff files, but supports decoding zip, gzip, arc, binhex, DiskDoubler, Compact Pro, lha, tar, uucode, and a number of other encodings and compression schemes you're likely to run into. One of the most indispensable Mac utilities around overall. Version 5.5 of Stuffit supports unzipping files in the Finder; you never even have to start another application.