A research team led by Christian Rutz of the University of Oxford mounted tiny cameras on the tails of crows to study their behavior in the wild. The study found that crows use tools (sticks, leaves, blades of grass) more extensively than previously thought. Crows were even observed carrying their favorite tool from place to place! Of course, now crows are using cameras to help researchers, too, which is strange enough in itself. Link
Update 10/4/07 by Alex: Here's the video: Link - Thanks Marilyn Terrell!
That puts them up there with humans and chimps as one of the very few species that can actually make tools.