Trampoliiiiiiiines!
Back when you were a kid, trampolines were an exhilarating mixture of aerial showmanship and constant risk of major bodily harm. These days they've improved on the original "deathtrap" design by adding protective walls, but it's still almost as fun. Your child may never know what it's like to stare death in the eyes, but will still get that weird falling feeling while trying to fall asleep.