US Netizen noted today that adding the -nonsensewords to the end of a search query results in the ability to see where your sandboxed site would rank if it were not sandboxed. An example query would be:
your keyword phrase -asdf -asdf -asdf -asdf -asdf -asdf -asdf -asdf -asdf -asdf -asdf -asdf -asdf
-asdf is simply representative of any nonsense word that would not show up on your page. But it seems as though there must be at least 13 of them for the filter to be turned off.
So, if you are curious what your ranking would be if you were not in the sandbox, try the search for yourself.
This seems to be proof that the sandbox exists - or maybe we should call it the filterbox for those people who hate the term sandbox. In any case, whatever you choose to call it - it exists.
The final questions remain: Why does it exist? What causes it? How can we get out of it?