I love both the ping pong ball brop and the standard bomb drop. But I really would dig the bubble machine if it would work on the plane. I have used my trainer both for bomb and or parachute drops as well as a glider tug. I have used a cradle or I have used a tow wire. The tow wire was a little more fun because the glider pilot has to fly his bird up to altitude instead of being just long for the ride.
I have also crashed with a glider on my cradle. Although I thought I could handle a cross wind it completely overpowered my rudder commands. Immediately after take off I was pushed into a strong right turn. I followed it around only to make a 359.5 degree turn whereby I released the glider as both planes were headed for terra-firma. It was hilarious because of a couple of reasons:
First. Everything was safe and well away from any other planes and or course, pilots.
Second. The ground was soft and did not damage either aircraft.
Third. I called out release as both planes were headed down (and only about six feet from the ground)
Fourth. Both planes hit like syncronized lawn darts....thunk..thunk![X(][X(]
Fifth. My friend and glider pilot just looked blankly at me after the crash...whereby I exclaimed "Didn't you hear me yell release???"
Sixth. The calm pause of astonished confusion on the face of my friend until I burst out in laughter.
Both planes were flying again the next weekend....albeit on a less windy day!
Dan