For quick and easy cartography, “My maps” service from Google allows to make and publish online maps.
A csv with coordinates can easily be uploaded. It also supports drawing of points, polygons and polylines on multiple layers.
Maps are easily modifiable using a smartphone: a must have for field cartography 🙂
Note that the export format is kml/kmz. The kmz exported can be unzipped with any zipping utility returning a kml. The kml can be imported directly in R using readOGR in the the rgdal package. It can also be imported in QGIS and from there exported to many formats.