I saved some money in 2014 when I built a Campy EPS (athena/chorus) group on my tt.
I saw in the internet a whole EPS group (so with chain, cranks, brakes) for 999 Euros for racing bikes which was cheap and which I bought. I sold the stuff I didn't need (brakes, cranks) and bought bar end controls separately. I do not need to shift on the brakes, so I only needed bar end controls.

Now there was one problem: there are two different interfaces (the interface is the small part you put somewhere on the cockpit from which the cables to the battery and the shiftters extend).
One for racing bikes with only two exits for the shifters (which I purchased thus) and one for tt bikes with four exits for the shifters (which is quite expensive to buy separately)

Now here comes the electronical "hack", which isn't really a hack by the way but merely an undocumented combination of parts. I asked myself if it is possible to combine the tt bar end controls with the interface I had (which was designed for racing bike controls). I asked at the hotline of Campagnolo and they said yes it should work and in the end it worked.

Pics are here here (post #3791):
http://forum.slowtwitch.com/...ng=official#p5333419