Web app Viamente Route Planner plots multi-destination routes for maximum efficiency. If you have a bunch of places you need to go to, and time isn't an issue, Viamente will choose the best route for you.
Unlike web app BatchGeo, which plots multiple points into a single Google Map, Viamente is a route planner for multiple destinations. Viamente is also helpful for delivery routes — the online service lets you add up to four vehicles and 24 different locations utilising Google Maps. (It's possible to add more, but you'll need to contact Viamente for an account.) Destinations can be plotted through the map toolbar, imported from an Excel template (which is available on the website), or from copying and pasting a list of addresses. Though it isn't a feature, the option to search addresses and businesses in Viamente would have been a nice addition.
If you are dealing with multiple vehicles, different routes for each vehicle can be plotted simultaneously. Viamente will estimate the driving time (and service time, if you're delivering something) for an overall estimate. Directions come in a printable format, for easy reading. Viamente is a free web app available online.