jQuery, Underscore, Backbone, require.js, text.js (require.js plugin), r.js (require.js optimizer) is the setup I've been using on new projects for about a year now and I love it. I love Backbone's models and collections. It took a while to come to terms with the get and set methods and nested objects is just a bit of a hassle (but that keeps me thinking twice about what I'm doing). I like the views but I find I'm repeating myself quite a bit and I've been meaning to extend Backone.View with a few conventions of my own, which is exactly the kind of thing Backbone was intended for. Require.js lets me modularize everything. the text.js plugin lets me keep markup in html files which get converted to JS functions during optimization with r.js. During development I have everything nice and separated for debugging and optimization before deployment jams everything up into 1 file. I have a bash script that generates a new project with the basic require.js config including shim settings needed for Underscore and Backbone and usually the localStorage plugin because that's real nice if you don't have actual services wired up yet. This setup is what made me start to enjoy front-end development.