While Gnome 3.6 hasn’t been released yet and it will take time till Distros adopt it, some extensions have already been released for 3.6 and they rock! It seems that we will see great things to happen in the next weeks on this area and is too bad that Gnome Extension page makes it hard to discover and use the extensions. Anyway..
Desktop Scroller (Left and Overview Version)
Just place the mouse on the left edge of the screen and scroll up and down. That’s all, a fast navigation thought workspaces. Works both in normal and overview mode. Simple idea, huge usability!
GS Supported: 3.6
System Monitor provides a quick launcher to Gnome System Monitor and also displays in real time two graphs (CPU, RAM).
DDT extension outdated :(
Such extensions obviously spend some CPU and RAM resources, so it isn’t really smart to load your Gnome with these if you run an old hardware.
Extension Page: https://extensions.gnome.org/extension/9/systemmonitor/
GS Supported: 3.4 && 3.6