From Homestar Runner Wiki
 Appearances of Different Aliens
- In Search of the Yello Dello — An unnamed alien uses the shower in Coach Z's locker room.
- Thomas is an alien friend of Teen Girl Squad member What's Her Face.
- Email narrator — Homestar Runner tells Marzipan she looks like an "enormous alien cow". Later, an Easter Egg shows a Powered by The Cheat scene featuring Marzipan as an "enormous alien cow" with Nebulon on The Moon.
- Rumble Red serves as a metaphor for communism in Old-Timey toons.
- Jibblies 2 Teaser — Strong Bad is dressed as a Xenomorph.
- Email buried — Strong Bad digs up a picture of a "babby alien" that, according to Strong Sad, Strong Mad drew when he was little.
- Email best thing — one of the main goals of Limozeen in their cartoon is to both run away from and give backstage passes to all the hot babe-liens of the galaxy.