Squirrels are all over. Quite honestly I don't pay much attention to them unless they run in front of my car. When I was a kid I also remember how friendly the squirrels were in the park near my house. They were very used to people feeding them. My neighbors who fed them thought the squirrels actually recognized them.
Now new research done at UC Berkeley shows squirrels are much more organized and sophisticated then we ever realized. They are capable of categorizing the nuts they find and sorting them by size and type so they can find them easily. Which is exactly what we do when we get home from grocery shopping.
The name for this ability is "chunking." Which really come in handy when you consider the average squirrel can gather and store about 10,000 nuts every year. That's about 30 nuts a day. Now I know why they're always rushing around.