SQL Prompt from Red-Gate.com is an awesome tool for reformatting your
SQL to make it more readable. It adds intellisense functionality to
SQL Server 2000 and 2005 (2008 has it built-in) as well as the
reformatting options. The reformatting is a huge reason why we use
it, so that all our SQL from all our developers uses a similar format
and each developer gets used to the standardized format.
Well formatted SQL is much easier to read, debug, and maintain and
there isn't anything built into SSMS to help with this.
http://www.red-gate.com/products/SQL_Prompt/index.htm
-Eric Isaacs