The foundry for Star Trek Online allows you to create your own missions. The tools available are quite comprehensive although not the full Cryptic toolset. Getting started is the tricky part but once you have the basic idea the only limit is your imagination. SRS has many member that have produced foundry missions, Irwin has produced the SRS Saga, a series of 12 episodes based on our fleet. Matt has produced the Iconian Trilogy which is continually listed in the top 20 foundry missions. David is our youngest foundry author, he stared when he was only eight years old. If you would like to get stared and need any help talk to us in chat or on the forums here, you may even produce trailers like this one for part three of the Iconian Trilogy.
STARBASE UGC provides resources, information, and tutorials for Star Trek Online user-generated-content