A lot of these seem really useful -- a nice set of things I've grumbled at having to write myself before as well as things that I haven't had a need for but I could very easily see being useful.

Out of curiosity, is there a reason you're actively marketing it as CoffeeScript helpers? For people using it as a drop-in library, it shouldn't make a lick of difference whether it's written in CS or vanilla JS, especially since you have the compiled JS in the GitHub repo. That isn't to say that you should be obscuring the fact, but right now the name says to me that being written in CoffeeScript is a significant part of the value being provided, which doesn't really seem to be the case.