Google Maps Engine!

QGIS, formerly Quantum GIS, is a user friendly open source Geographic Information System (GIS) licensed under the GNU General Public License that runs on Linux, Unix, Mac OSX, and Windows and supports numerous vector, raster, and database formats and functionalities.

MapBox makes it easy to design beautiful custom maps, and fast to integrate them into websites and mobile applications using Open Street Map data.

A location intelligence and visualization engine that empowers you to effortlessly transform data into insights. With CartoDB, connect and map location data, quickly customize your visualizations, and develop powerful location based apps.

Creating web map applications with Mango is quick and easy. All you need is a web browser and your data. What you won't need are any programmers, expensive servers, software licenses or an accountant to figure out the pricing.

Mapline is the simplest mapping software on the planet! Be empowered with map visualizations from Excel spreadsheet data to optimize logistics, enhance market planning, identify growth opportunities, or mitigate market risks. Create your first map now!

This is an online mapping site that "helps you make static, thematic maps from geographic data by bringing the best of traditional cartographic design to internet map-making." Sponsored by Axis Maps, LLC.

What3words encodes geographic coordinates into 3 dictionary words (for example, the Statue of Liberty is located at planet.inches.most). what3words is different from other alphanumeric location systems and GPS coordinates in that it displays 3 words rather than long strings of numbers or letters. what3words has a website, apps for iOS and Android, as well as an API that enables bidirectional conversion of what3words address and latitude/longitude coordinates.Source: Wikipedia

MapET Spatial Feature Server is software that makes your geographic information (vector data) available to others in your organization and optionally anyone with an Internet connection. This is accomplished through web services, which allow a powerful server computer to receive and process requests for information sent by other devices. MapET Spatial Feature Server opens your GIS to devices that can connect to web services.