Google maps now lets you plan journey itineries by showing routes with multiple destinations for a single trip.
You can add as many intermediate stops as you like, and can drag and drop the order of each stop to have Google recalculate the suggested route. Very. Nice. As far as I know Google's the first online mapping destination to provide this kind of functionality, though similar things have been available for GPS units in the past.
There's also a newly added, tiny little gray arrow, that sites half way down the page between the map and the directions. Clicking it will hide the directions 'full screening' the map. This is a nice touch that I've been waiting a while for.
In any case I've now got my trip to Cornwall for Christmas plugged in -- including the stop at Stonehenge for good measure.