SQL Server Management Studio
I installed the MSSQL 2005 client, named SQL Server Management Studio.
Before that, I was using the Enterprise Manager that comes with SQL 2000. It is a piece of crap, but one of the only options if you needed to do manual read/write in a MSSQL server.
This new version accepts Transact-SQL, MDX, XMLA, XML, SQL Server 2005 Mobile Edition queries and SQLCMD commands.
Most notable was the interface changes. All renewed. This new version looks more like Office 2003 and VS2005. The browsing is very superior to the SQL 2000 client.
Finally I got rid of the old Enterprise Manager!