Well, this isn't really a website of the *week* anymore, is it? I should find a new name for it. Anyway, SensibleUnits.com is the website and it is pretty darn neat. You basically plug any measurement into it and it will tell you how large that is in "real" terms. For example, 20 yards = 2.2 London buses end to end. 500mm = 4.2 CDs side by side. I could spend all day playing with this. And now I have infected you too!