Sprokets

[Apr 21 2005]

Exploding Tree (+3, -7)
Hide-And-Seek Game Citywide (+2, -2)
Meter Feeder 2 (+5, -1)
Multi-door elevator (+4, -2)
Personal pay-per-lift elevators (+1, -3)
Traffic light transponder (+3, -4)

random, halfbakery