Admin command forcing the player to take a screenshot. This can be useful I think. This was (and it is still) used in CS 1.6 and it works brilliantly. For example, a player is suspicious for aimbotting or cheating with something, admins can force him to take screenshot (and after that ban him) and then request that screenshot to be posted in the unban applications section, if the player is clear he'll get unbanned. I don't know if this could be scripted but it'll help admins and players.
You took CS 1.6 as an example. I believe that after they force screenshot him they ban him only if the picture is black, because hack rejects taking pictures. Same goes with Punkbuster in Call of Duty series.
Also Nitin said, it isn't bad idea, but I don't think this can be added.
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