Shimano Chainring Wrench
Shimano Chainring Wrench offers the professional or home mechanic an easy to use, all-in-one chainring wrench, without the hassles and dangers of sockets and standard allen key, which can easily strip out a torx nut. Take care of your latest-generation Shimano crankset with the tools the factory race techs use, Genuine Shimano.
I thought this tool was long but actually it was short, very disapointed. Though I know this is for chain rings I am sure you can use it for stems, headset cap and other components.