Jamie Bamber (Battlestar Galactica, Hornblower)
John Rhys-Davies (Lord of the Rings, Indiana Jones)
Some of the people I've met weren't doing posed photos so I don't have a proof for those, but here's a few of the other people I have met.
Connor Trinneer (Star Trek: Enterprise, Stargate: Atlantis)
Ray Park (Star Wars, X-Men)
Rene Auberjonois (Star Trek: Deep Space 9, Boston Legal)
Anthony Head (Buffy, Merlin)