Goa'uld holographic projector
From The Stargate Omnipedia
Device believed to be constructed by the Goa'uld Nerus, capable of relaying a variety of information. Projectors can gain their data from Goa'uld spy satellites in distant parts of the galaxy.
KEY EPISODES
Seth - Jacob Carter / Selmak use a holographic projector to show SG-1 and General Hammond the Goa'uld family pyramid.
Exodus - Samantha Carter and the Tok'ra use a holographic projector to outline their plan to detonate Vorash's sun.
Fallen - The Tok'ra bring a holographic projector to the S.G.C. to give a detailed analysis of Anubis's mothership.
Beachhead - Nerus uses a holographic projector to show the advancement of an Ori force field on Kallana.