Microsoft recently released a nice little add-in for SQL Server Management Studio (SSMS) called SQL Server 2005 Performance Dashboard Reports, which uses the custom reports feature of SSMS. It allows you to easily monitor some key performance metrics (using DMV queries under the covers) from within SSMS. You can download it here. It does require that both the server being monitored and the machine where SSMS is running have SP2 installed.
Technorati Tag: SQL Server