Trabajar con ficheros Zip desde .Net
Se ha publicado en codeplex una libreria desarrollada para facilitar el trabajo con archivos Zip.
Project DescriptionThe Microsoft .NET Framework {v2.0 v3.0 v3.5} includes base class libraries supporting compression within streams - both the Deflate and Gzip formats are supported. But the System.IO.Compression namespace provides streaming compression only - useful for communicating between cooperating parties but not directly useful for creating compressed archives, like .zip files. The built-in compression library does not know how to format zip archive headers and so on.
This is a simple class library that augments the System.IO.Compression.DeflateStream class, to provide handling for Zip files. Using this library, you can write .NET applications that read and write zip-format files.
http://www.codeplex.com/DotNetZip