I was recently introduced to BatchGEO (batchgeo.com).  It is a mapping service which will plot multiple locations on a map based on address information compiled on a spreadsheet.  The home page allows you to paste records directly on the page or to download a spreadsheet template to import later.  With your data loaded on the web page, you can click the Map Now button and all the locations will be plotted and displayed on a map.  You can save the map and a link to the map can be shared with other folks.  A bonus is when the map is emailed and opened on an Android mobile device, driving directions are available.