Now it's not just chimps (link), but dogs are making choices too. (link) And, interestingly, dogs are behaving more the way humans should (sometimes even than humans do)!
The articles are interesting from another point of view, though, than just as evidence that "free will" (if you simply mean the ability to make choices) is present in other creatures besides man. The articles are also an interesting form of opposition to evolutionism. How so? Dogs apparently have a choice mechanism that is more similar to humans than the choice mechanism of chimps. This means that evolutionism has to make yet another appeal to parallel ("convergent") evolution or re-nest the hierarchy. Either way, the special pleading becomes more evident.