The hungriest resource eater by far is the MySQL database which stores and runs this messageboard; it is forever getting larger and larger and I imagine if/when we do move over to a dedicated server it will be because of this growth. The actual disk space for all the tracklists and other components only amounts to 8GB tops. For convenience and bandwidth issues we locate all our audio for this messageboard in Denmark with thanks to FuzzY-LogiC's dedicated server over there for which we are eternally grateful.
On the other hand, the BBC's various archives for sound and vision are too huge to imagine, but then again they are split up into different sections. Their sound archives go right back to the early days of radio, but I believe that since about 2003 they no longer archive every single minute of every single radio show, at least, not on Radio 1 (i.e. the quality is just not worth saving!).