Size Matters...when it comes to starships that is

Over at io9.com, wordpress blogger Invader Xen (his astronomy blog http://supernovacondensate.net/) created a size comparison of the Federation Enterprise and real-world space vehicles, and this is his imagine, and quite good work...visit his blog, also very good.
Size with starships is one of those things that is hard to judge for us sci-fi writers, often we, especially for RPGs, make these space warships massive. Many years ago, it was not uncome for me to design warships in the battlecruiser class being 800-1000 meters.