This is my conversion of the Todos example to coffeescript. I also tidied up the file structure (according to what I felt makes sense), and tweaked some of the functionality.
Assuming the good folks at Meteor haven't included that in the main repo yet, you also need to pull a specific commit from Jason Giedymin's fork. Instructions to pull a given commit from a fork are here.
In short, after making your own fork:
> git remote add jasongiedymin git://github.com/JasonGiedymin/meteor.git
> git fetch jasongiedymin
> git cherry-pick 6452d98bf3678ab56fe840ae65f5a6d45b18e353
Then install:
> ./install.sh
If you don't do this, CoffeeScript will, by default, wrap every file in (function() { ... }).call(); which will make global variables (like the MiniMongo LocalCollections) invisible outside of the file they're defined in.