Last year I (along with the rest of our Node Knockout team) built a game that had a pulsing dot similar to this one. We used Raphael (SVG/VML). Although it's much heavier than this using Raphael is cross-browser. It might be a suitable fallback.
I want to open source the whole project but haven't had time to clean it up.
My suggestion: don't bother cleaning it up, just publish it. If the two realistic options are your code dropping off the face of the earth because it's never published, or it being put in a place where someone might find it useful and run with it, the latter is far more beneficial to society.
If you're concerned about your personal reputation (which in my experience tends to be the case) then consider you're likely better off as a prolific coder than a sparse one, and if anything we should be pushing the industry towards more open exchange of code so as to reduce loss & waste.
I want to open source the whole project but haven't had time to clean it up.