I spent all day Tuesday attending a session on indexing with Kim Tripp. I really learned how much I did not know about indexing for sql server.  It really gave me some things to think about.  I can not overstate the need for clustered indexes on every table in your database.  She has really good reasons for putting an ideentity column on very table and using it for the clustered index and many times the primary key as well. You can argue about how this may violate some normalizatio rules, but the performance gains and maintainance issues it solves were incredible.  If you get a chance to hear her speak try to attend the session.