Leaflet.js by default supports Cloudmade’s awesome map tiles. The Open MapQuest project also provides beautiful tiles, which are now used at OpenStreetMap.org. To use these tiles all you have to do is to change the map preamble as follows.
The Cloudmade maps layer looks like this.
Change the preamble to.
Pingback: MapQuest tiles through Leaflet.js « geohacker's randomness