If you have used up the cereal boxes for cereal box birds, but are not yet tired of them you can continue with plastic bottle birds :)
Of yourse you can also make plastic bottle bird feeders from the plastic bottles – and that put the cereal box birds in ;-)
Links:
Plastic Bottle Birds (Plastic bottle bird)
Here at unikatissima:
Cereal Box Birds
Plastic Bottle Bird Feeders