It’s called “Gnome-do” and it’s freaking amazing. I have to get used to Linux again, since I’m currently doing IT work and all the best easily customized network monitoring tools only exist on Linux, I’m playing around with configurations I like. Holy Linus Torvalds, this thing is awesome.
It does have a few quirks, but overall, it’s pretty neat. I’m running Ubuntu right now and it works pretty well. It’s not the same as a “dock,” although you can use it as such through Docky, which is how I am running it.