I had wanted to play with the Gooey Effect for some time. I decided to use React for this so I rewrote some of the code from the below forks.
Once the rewrite was complete, I played with some numbers and found this interesting aesthetic effect. The spinner I think is rather compelling. Would probably do a couple more iterations on it before I considered using it in a product though.
The things that are important to take note of in the rewrite is how you use could refs to manage what portion of the UI is handled with d3 and what is managed with React.