Small scooter for up to 2 minifigures. With controls, windshield, 2 gear attachment points and a cannon that can also hold a pole.
Instructions (includes part list)
I struggled for a long time, trying to build a machine around the special wedge part with a cut-out. So I tried to create a minimal playable design. The boat stud twiddles nicely with the center of mass, yielding interesting/shaky ride behavior.