Free Tools for Terminal Servers
Part 1 of a series. The usual suspects are there:

MS:

• LSReport & LSView for enumerating list of MS License Servers
• TSECMD for managing Terminals Service via the command line

Citrix:

• DSCheck for validation checks on the Citrix Data Store
• QueryDC for querying the Data Collector of the farm
• QueryDS for determining the DC in a specified zone
• DSView for viewing specific record in the Data Store
• Qprinter for monitoring the progress of printer drivers

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UPDATE: Here's Part II

Here's a similar article by Brian Madden, More...