Vsi Builder is an extension for Visual Studio 2012 which allows packaging code snippets and add-ins into the old-style .Vsi packages, since they cannot be deployed via the new VSIX format.
You simply add a list of additional contents, like snippets and add-ins, and then you build your redistributable .Vsi installer. With Vsi Builder you can

1.package, deploy and share Code Snippets and Visual Studio add-ins (not extensions) who are not supported by the VSIX format
2.add End User License Agreement to the packages
3.add a digital signature whenever you own a digital certificate
4.uninstall previously installed contents

Portions of this extension use the DotNetZip library.

The full source code in Visual Basic 2012 is available at:http://vsibuilder.codeplex.com

You first load your contents in to the tool window:

Next you build your .Vsi package that you can share with other developers and easily install the additional code snippets and add-ins: