TSGrinder
TSGrinder is the first production Terminal Server brute force tool, and is now in release 2. The main idea here is that the Administrator account, since it cannot be locked out for local logons, can be brute forced. And having an encrypted channel to the TS logon process sure helps to keep IDS from catching the attempts.
TSGringer is a "dictionary" based attack tool, but it does have some interesting features like "l337" conversion, and supports multiple attack windows from a single dictionary file. TSGrinder also supports multiple password attempts in the same connection, and allows you to specify how many times to try a username/password combination within a particular connection (the default is 5) . This is used by hackers to help avoiding detection, because by default after 5 unsuccessful logon attempts, the Terminal Server ends the connection and an event is logged to the Terminal Server event log.
Note that the tool requires the Microsoft Simulated Terminal Server Client tool, "roboclient," which may be found here:
ftp://ftp.microsoft.com/ResKit/win2000/roboclient.zip