Just received a newsletter this morning, Pushys is having a sale on the Stages 105 5800 crank power meters. Good local alternative to this other deal from PBK.
Info text credit to 2ndeffort
For anyone who doesnt understand what this is it is a crankarm for a road racing bicycle that contains a strain gauge and can keep track of how much power you are generating through your legs (well, as it is only for the left crank, 1 leg). This suits a 105 5800 groupset
DCRainmaker's Power Meter Buyers Guide (includes info on what a power meter does)
Direct link to DCRainmaker's Power Meter Buyers Guide section on Stages Power Meters
But I usually use my right arm. Is there a version that can measure my strain and power on right side?
Oh wait.. this is a cycling thing? Nvm.