A month or two back I tried out anodizing a titanium bicycle fork. Eventually I want to anodize, mask, and bead blast a frame along the same lines as Firefly , so the fork was a test-run to get a feel for the anodizing and masking process.
I did the anodizing by soaking a foam brush in a water and baking soda mixture, clipping one power supply lead to the brush, and one to the part, and brushing the part.
If you're good at this, you can get nice gradients by adjusting the power supply voltage as you move along the part, but I definitely need more practice. I love the purple and dark blue parts:
I used some vinyl tape to mask out a pattern, and then bead blasted to strip the anodizing where it wasn't masked. I didn't put any effort into this pattern since this was a test, but eventually I'll make a mask on a CNC vinyl cutter. I need to find a blasting cabinet with a gentler media in it as well.