I was checking out Technic to see how can I put an anti-Technic mechanism on my mod, when I found "TechnicBridge". Some class inspection and texture looking immediately suggests - it is Power Converters.
Now, where's power crystals?
If I remember correctly (Since I can't check now, since SA hid their MC thread from non-members). Powercrystal coded the converter directly for the Technic pack, then released it as a stand alone add-on on the MC forums/IC forums. I could be honestly mistaken though, since it's been quite a while...