LazyJS – like Underscore, but lazier (2011) (danieltao.com)

Reading this was what made lazy evaluation "click" with me. Interestingly for those familiar with the JavaScript library wars of the 2010s, IIRC this is what made John-David Dalton incorporate laziness into his Underscore-killer, LoDash.

I used lazy.js for a few projects and loved it.