I really got used to NuGet in the last year and I have almost completely forgotten what is ‘manually adding library file reference’ (can’t say I regret about that). So I was a bit disappointed when I found out that the well-known SharpZipLib NuGet package can’t be used with WP7 projects. However, there is a nice SL/WP7 port version of this library on codeplex (seems that it is abandoned though – no updates in ~2 years, but it works). It was not available to the fellow NuGetters.. until now. Use
There is also a package mirror at BitBucket. Happy zipping!