Here's my latest Thunderfire Cannon, made from the HITECH Hellfire Cannon (reviewed here). It didn't have any good places for freehand, so I just went with my standard Executioner paint scheme to link it in with the rest of my army.
And here's the old school Techmarine with his uber-power fist.
This is getting me close to my planned army for the Imperiad GT. I still need a mounted Chaplain, another Tactical squad, and a new Stormtalon. Since I only have the materials for the mounted Chaplain currently, he'll be my next project.