If you use Sql-Server, then you must get SqlComplete for its awesome intellisense that it provides within Sql Server Management Studio (SSMS).
One of the best things I like about it: Regular SSMS intellisense will not work in SqlCmd mode. SqlComplete works even in SqlCmd mode. (And for me that’s huge, because I open all my query windows by default in SqlCmd mode). In addition it provides you with the ability of formatting your entire t-sql document (awesome!).
SqlComplete has two editions: a free edition that has reduced functionality (Not as great document formatting capabilities) and a standard edition that costs $99 (edition differences). I really wished that they had a personal edition for $50, cause I would definitely buy this tool.
Also remember to install the other awesome SSMS add-on: SSMS Tools, which provides some other useful features that make SSMS a pleasure to work with.
SqlComplete – Alternative to SSMS intellisense: http://www.devart.com/dbforge/sql/sqlcomplete/alternative-to-ssms-intellisense.html