THEY'RE TOTALLY RIPPING OFF ALIENS WITH SIGOURNEY WEAVER. This was before I was awarding bonus points for 'cringingly obvious references'.
I hate this episode so much. It's a Trojan Horse episode disguised as a Plague episode.
It features the last Sneeze from Daniel Jackson, the first Ha'tak, the first mention of NAQUADAH, and the last intelligent thing Jack O'Neill ever says about astronomy.