The Rafflesia
A very tedious intersection based on the magic roundabout principles. Build it in your city, and watch your Cims weeps as they try to navigate their way past this monstrosity.
This intersection was designed for RIGHT-HAND roads. I have no idea what happens in left-hand cities, so feel free to comment if nothing terrible occurs (or the opposite! :P).
1) Mostly for small cities with well-defined blocks. I can see heavier traffic clog up the system quickly (unless the upcoming Traffic++ mod update helps improve the situation).
2) Traffic++ not required, but definitely would help if you manually wire which way the traffic should flow. See the screenshots in the gallery. On the off-chance that the game spawns traffic lights on the roundabout, use Traffic Manager to remove them.
3) The 6-lane sections of the outer roundabout is for you to place bus stops. Ideally it should act as a convoluted bus hub, so buses come in and out from their respective entrance to different blocks of the city. See the video. If done properly, buses will have very minimal interaction with the roundabouts.
4) Buildings can be placed at the 6-lane section, but requires Road Anarchy mod if you want to place service buildings there (so that your services have instant access to all parts of your city)
5) If you have trouble plonking it down, then Road Anarchy and NoPillars mod may help.