I am currently running a campaign for three club members using Google Maps (so you use the real world which means no drawing up maps and is pretty realistic
). The way this works is as follows. I pick a part of the world (the UK), and save four versions of the map (Umpire & one for each of the 3 players). On the Umpire's map, I plonk a number of objective flags in various places around a central location (the West Midlands, as this happens to be home). I then draw up the army lists for each player and locate their armies at an equal distance from the centre point (ie. south wales, suffolk and yorkshire). Each unit is given its own marker on the map. I then open each player's version of the map and add the objective flags and their own unit markers.Each player is emailed the URL of their own map and can see where their units are located. They then send orders in, which I process on the central map and reflect moves on each of the players' maps. When moves have been made, players are each sent a summary and the URL of their revised map. It takes a while to work through a turn (making sure unit locatios are correct on both the Umpire and Player maps) but has worked well so far.