Little green alien that's ready to party.
Another purple, slug like alien (or possibly just a monster) pointing to the left.
Small alien face in the style most typically seen in movies.
Pink martian with huge teeth and one big eye.
Another friendly looking space creature, this one is green with antennas.
Little yellow alien hitchhiker with a sign "Going my way.."
This one with flashing eyes looks best on a dark background.
And a tiny green alien in a spaceship passing Earth.
Bright green alien holding his (or her) hand in the peace sign, with saturn in the background.
An alien tourist, This one reminds me of the alien from the movie "Paul".
This one looks to me like the image of an alien from an old fuzzy TV show.