An example that shows a CartoDB layer with Leaflet.js. A lot of different tile services are compatible with Leaflet: click here for a list with live previews.
Modified http://d3js.org/d3.v3.min.js to a secure url
Modified http://cdn.leafletjs.com/leaflet/v0.7.7/leaflet.js to a secure url
https://d3js.org/d3.v3.min.js
https://cdn.leafletjs.com/leaflet/v0.7.7/leaflet.js