i need ideas for a halloween costume...any suggestions?

here's my criteria:

• i may be going to a concert, so something cute and comfy and not too warm
• nothing that involves spandex
• anything inexpensive or that i can make from existing clothes
• nothing skanky...i don't live by the rule that Halloween is the one time a year girls can dress like skanks and get away with it!
• Creative!

Ideas? Come on I know you have some!!! Amy-you're creative...gimme something!

Thanks!