I am horrible at origami, but maybe you could do a really big paper crane? Like the size of a dinner plate, I think that would be really cool. Just a sec, let me take a looky loo on you-tube :) (for the crane: http: http://www.youtube.com/watch?v=FSijU52XJ7w )
Origami butterfly (not sure how 3D) http://www.youtube.com/watch?v=X4L5nDDgEEk
This is for origami fireworks: http://www.youtube.com/watch?v=p9xKxEV1FkY
This is for a bird, kind of like a penguin, but not. http://www.youtube.com/watch?v=p9xKxEV1FkY
This is for a frog, he's not so big, but still. http://www.youtube.com/watch?v=rc9lVHvfzMY
This one might be tough, but pretty cool: Dragon- http://www.youtube.com/watch?v=XvFisaAsz8o
And here is the youtube channel for origami :) http://www.youtube.com/topic/-vQM4xQJwXg/?feature=results_main
Hope I helped :) :) :) Even just a little bit :)
