Stuck at red lights
The magnetic red light changers do work. I have one called RLC-40 from redlightchanger.com that's the most powerful made, with a lifetime warranty that's coated with epoxy, and use it correctly by tracking your cycle right over the sensor wire marks on the pavement. I never get stuck waiting for red lights again, unless the traffic light is broken. Then all you can do is notify the local traffic department.