Going back to my post about dog parks, a really great thing to take with you is a ball thrower. These are really good for people with a bad back or joint problems who can't bend down to pick up a ball. They're also good for people who don't have as much energy as their dog. The dog does all the hard work. Picking up a ball after a rottweiler has slobbered all over it isn't a pleasant experience (no offence to rotties). I've experienced this many times and I took to wearing gloves to avoid the problem. The ball thrower is brilliant idea. If you want to get one you'll find them at the pet shops and they're probably available on the internet as well.