What I've done is made what I call a HyperRoller. It's out and back hypercoaster type layout, without the coaster car. I use the Big Ball Machine (BBM) balls on a special track with that orange plastic stuff that the balls roll on. (If you have the bbm set, it is similiar to the part where the balls do a loop)Anayway, I usually build a lift system similar to the bbm, have a major first drop followed by a cammelback, drop, turnaround, and bunny hops. Really fun to design your own layout, it takes a lot of trial and error.
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-Josh