Ever wanted to compare the British Empire at its height with Imperial Rome (without, of course, playing a video game pitting legionnaires against Redcoats)? Online database FindTheData has an interesting feature which allows you to compare the vital stats of major empires throughout history side by side (here's London and Rome by the numbers -- Britannia at its height controlled an area nearly six times larger than Rome -- which, remember, ruled most of the Europe and the Near East at its peak).