trampoline

For just a few bucks you can turn your backyard trampoline into your backyard swimming pool. If you know what you're doing.

For anyone who has ever taken batting practice before, this video is a must-see. I've hit baseballs off a tee, soft-tossed to me,  and thrown to me from the pitcher's mound. However, I was never an accurate enough hitter to perfectly place balls off of a trampoline.