[ZenGum]

Some things - street numbers, numbers of posts in a thread, lend themselves to a natural explanation of the preponderance of lower first digits. This is becaue they are built in a series - you can't have post 3 without post 2, but you can have post 2 with no post 3. So there will be more 2-post threads than 3-post threads.

Interestingly, though, it works just as well with things like river lengths and mountain heights, despite the fact that you CAN have a 3 mile long river without having a 2 mile long river. Weirder still, it holds up just as well no matter what units you measure in. Feet, meters, inches, whatever.