Underscore.js is a 'utility-belt library' and it makes it a breeze to solve many of the common problems you'll see when working with jQuery.
Dan will have some interactive examples to show how jQuery and Underscore can work together to save time and headaches. Wading through an AJAX response? There's a function for that... Laggy scroll listeners? There's a function for that too!
Thinking of coming? Add yourself on Lanyrd