On the set of Stargate SG-1 it was an in-joke that Martin Wood (director) and Dan Shea (stunt coordinator) would often walk around with oversized wrenches in the background appearing to do work. In the season 5 episode "Red Sky" they both appear.

Since I'm aware of this now, I keep noticing them in new places on every rewatch!

#TV #SciFi #Stargate #StargateSG1

In the season 3 finale where O'Neill gets beamed out from the corridor of the base while talking to Carter, Martin Wood is in the background. In the first episode of season 4 when a similar scene appears, and O'Neill says "Deja Vu", I'm pretty sure it's Martin Wood again walking behind him, although this time he's out of focus, so it's harder to tell.
@veronica Martin Wood put himself in nonspeaking cameos on regular basis, like in a crossword puzzle scene in “Lost City”. Peter Deluise did the same when he stared directing.