craftgrrl | Yes we're going to a party party.

Good morning, lovelies! I need your help!
My boyfriend's birthday is on Thursday, and i have been placed in charge of the festivities. Since he likes old science fiction stories (heinlein, asimov, etc), we decided upon a science fiction theme. So far i am pretty hard-pressed for ideas, though i am definitely going to make a robot cake. The party is going to be at my house, we are going to decorate the living room according to the theme. I was thinking about drawing, on carboard, a bunch of rocketships and spacemen and martians and such and putting them on the wall. Also, i work at a Hobby Lobby, and they sell astronaut ice cream, so we were thinking about serving that, too.
So, other than that, do you have any suggestions? And does anyone know where i could ifnd some retro-ish images of martians, etc to copy for decorations? Any help would be much appreciated.
♥