The best replacement for handlebars is mustache.

The best alternatives to handlebars are rated as following:
★★★★★  mustache
★★★  underscore
★★★  jade
★★★  angular
★★★  dust
★★★  hogan
★★  ejs
★★  knockout
★★  backbone
★★  clip ons
★★  aluminum handlebars
★★  twig
★  haml
★  jsrender
★  drop
★  dust js
  swig

Your alternative for handlebars is not listed? Suggest!
Speaking about handlebars, one probably shouldn't forget about backbone.

Other search terms related to handlebars and their ratings are:
★★★★★ backbone
★★★★★ express
★★★★ angular
★★ knockout
★ internal throttle
★ express js
★ jquery mobile
no handlebars
You have in mind a companion for handlebars and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of handlebars in all years. Click on graph for more.
handlebars
mustache
underscore