redirect-ie-7-lower
Simple package that redirects a user on IE7 or lower to a page, public/noie.html. An example gist of such a page is also available.
The original use case was that some of my smart packages were breaking my project, and I was only getting back a blank page on IE7 or 6, and I wanted to at least explain to users why things weren't working.
Make sure it is placed as early as possible in your Meteor project's smart.json so that it gets run before other packages that are causing issues with the earlier Internet Explorers.