GMaps.js allows you to use the potential of Google Maps in a simple way. No more extensive documentation or large amount of code. GMaps is compatible with JSON formatted data which you can utilize to integrate your map with a particular app, like Foursquare.
With jHERE, you can easily add interactive maps to your website. In only 4KB, you get a powerful map API, highly customizable markers, event handling and info bubbles. Bonus features are KML support and data visualization via heatmaps.
DataMaps is a script to display any data interactively and beautifully inside maps. It comes with ready-to-use maps for world map with countries, USA with states and a combined one. The map data is stored as JSON and any custom maps can be created by following the structure. DataMaps makes use of D3, Backbone + Underscore and comes as a jQuery plugin (or a as a standalone Backbone view).
9. OSM Buildings