Need some help deciding something...

[CountArach]

This may sound like a strange request but I need an idea for what to go as to a party. The theme is "What you wanted to be when you grew up", but of course no one is going as what they actually wanted to be (How am I supposed to dress as an historian? ). I am drawing complete blanks on ideas, so I thought I would chuck it over to you guys. Just a few conditions:
1) Fairly cheap
2) Easy
3) Possible to dance in
4) Suitable for warm temperatures

So go nuts! If I like it I'll go and take pictures.