Look at here. 3D printing in 3D (e.g. no traditional slicing !!) with Z-axes going up and down !! It is using Cura, but I would like to have the same with skeinforge…
I would like to raise a question to the owners of an Ultimaker printer that can try it: “How can you prevent that the object crashes the bottom X axes of the hot-end, while lowering and trying to reach a too deep Z position ?” I suppose that not all objects are adapt to be printed in this way…
Another comment is that with this technique you are able to print a SMOOTH pyramid or any angled shape without steps !!!
There are still layers, all you’re preventing is the layer boundaries that cause little surface marks if your hotend oozes.
Well… I have a 4 axis CAM we can build on. To get even more 
Tool collision I not difficult if you can model your tool out of specific primitives and are limited to models made out of triangles anyway.
This will only work for the outside surfaces and will only work at very slight angles. The best you could hope for is angled/curved surfaces that look similar to vertical surfaces do now. An articulated head would be required for any angles over a few degrees. The slicing/cam software would be much more complex to choose the proper paths and to avoid crashing.
“It is using Cura, but I would like to have the same with skeinforge”
Cura basically IS skeinforge. Cura uses skeinforge/pypy (JIT Python Interpreter) as the back end slicing engine. Also, for those who think Cura is Ultimaker only; it’s not. You can use it on your reprap too. 
Thanks for the info. I will have a look!
Why has it been halted?
does it really bring that much compared to, let’s say, slic3r “continuous Z” allowing to move progressively along Z instead of doing the regular slice moves ? I can see the point with multiple hotends maybe, but that’s mostly it.
I guess I should download the new Sailfish firmware and see if it actually supports other slicers.
That spend a week to get all the parameters calibrated, so a 1mm hole actually has 1.0mm after I us cooled down.
I think they omitted Cura because they didn’t know it existed. Cura is very well known within the Ultimaker community. But less within the RepRap community, and even less on the Makerbot side.
@Jelle_Boomstra not their competitors.
Both printers are hardly supported anymore (certainly no new firmwares) and Sailfish is a community firmware.