Hulsroy's Hustle

Hah! That's interesting. I'll have a think about that solution. My gut feeling is that no way would that work, but maybe that can be overcome with some ghetto engineering.

Looks quite similar to the Montague Biframe system, although there, the whole seattube turned.

to do that idea, i guess the chainset would need to rotate with the rear section unless you wanted to remove the chain when folding?