Here's a rough transcript of the Hangout that Peter Jackson (PJ), Richard Armitage (RA), and Evangeline Lilly (EL) were in a few منٹ ago. The quotes are not exact quotes, but rather, summaries. There is also a transcript of the new clip that was shown, the beginning of the barrel rider scene.

Q: Any pranks on set?
PJ: Ian McKellen loves napping, so I once sneaked up on him while he was napping between takes and yelled "And...Action!" causing Ian to jump up in surprise and straighten up as if he had to act.
EL: There wasn't really much time to do pranking; the best pranks take place on camera,...