What commands are available to visualize the data pages on SQL Server? From msdn:


  The page is the fundamental unit of
  data storage in SQL Server. An extent
  is a collection of eight physically
  contiguous pages. Extents help
  efficiently manage pages.
  
  This section describes the data
  structures that are used to manage
  pages and extents. Understanding the
  architecture of pages and extents is
  important for designing and developing
  databases that perform efficiently.


So what commands/utilities are available to visualize the data pages on SQL Server ?
DBCC PAGE

Paul Randal also has lots of stuff about on-disk structures and articles "Anatomy of a (insert storage thing here)" (some overlap here of course)