How I do one-off front-end templating with Handlebars, HAML, and CoffeeScript.

_instagram_thumbnail_handlebars_template.haml

%script#instagram-thumbnail-popover{type: "text/x-handlebars-template"}
  %img{src: "{{images.low_resolution.url}}"}/
  %i.icon-heart/
  {{likes.count}} likes

%script#instagram-thumbnails{type: "text/x-handlebars-template"}
  %ul.thumbnails
    {{#data}}
    %li.span1
      %a.thumbnail{href: "{{link}}", title: "{{caption.text}}", data: {content:"{{> popover}}"}}
        %img{src: "{{images.thumbnail.url}}"}
    {{/data}}

instagram_templating.coffee

$ ->
  Handlebars.registerPartial 'popover', $('#instagram-thumbnail-popover').html()
  instagram_template = Handlebars.compile $('#instagram-thumbnails').html()

  $.getJSON "/instagram/#{instagram_handle}", (response) ->
    instagram_html = instagram_template response
    $instagram.append instagram_html
    $instagram.find('.thumbnail').popover placement: 'bottom'

Not advisable to compile templates at runtime at any sort of significant scale, but works great for single page apps when you can compile templates one at time, as needed, on the fly.