A brown bear was spotted and photographed using a rock to scrub itself.
BBC Nature - Brown bear exfoliates using rock as a tool:
"The finding makes bears the fifth non-primate mammal known to make use of tools.
Sea otters use rocks to smash the shells of sea urchins and clams, Asian elephants have been witnessed using tree branches to swat flies, some bottlenose dolphins use sponges to cover their rostrum while foraging and humpback whales have been known to make use of bubbles to help them trap groups of fish."
Why is this a big deal? Because tools used to be regarded as one of the main markers of humanity. Using them has been seen as a symptom of that ill-defined quality, intelligence.
Discoveries in recent years have steadily increased membership in the tool club. Besides the mammals listed above, we have anecdotal reports of raccoons using rocks to smash crayfish. Some birds have been proved to use tools--for example, the crows use blades of grass to probe for insects. Bernd Heinrich even witnessed a wasp using a twig to tamp mud. My guess is that there's a lot more intelligence on this planet than we ever suspected.