lol we got those. i took the tennis ball off. attacked it to the end of my sabre and used it in a fun bout. middle way thro i flicked and it came off my tip and flew and hit my partner striaght in the nuts. lol he couldnt stand up for 20 mins
An addition to the above listed drills, get a partner! I know, sometimes you don't have one. But I never had the patience to stand there and do ball work by myself.
But with a partner, someone starts off, extends or lunges to hit it (toward the other fencer) who retaliates in kind. It a heck of a lot harder to hit, and you can hit it moving toward or away from you. You can keep score, you can chat, you can try to hit it quick and fast so they can't hit it. But its fun!