I received a fun Forever Knight/The Listener/Flashpoint crossover, Puncture by greerwatson, in which an adult Lisa Cooper encounters a figure from her past and the IIB. (You don't have to be familiar with Flashpoint to follow the story, but some knowledge of both Forever Knight and The Listener--or at least their basic premises--would be helpful.)
My own story for the exchange was Ghosts in the Corridors, a Being Human Nora & Sally friendship story from early in the second season.
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