No, this wasn't inspired by Jurek, I've been waiting for it to all come together for a while longer:
Orignally an S1R, with Kinetics XRF8W hub kit and Spa XD2 double crankset (in order to get the all-important 160mm crank length). The extended Kinetics chain tensioner means the outer ring is usable for flatland/descending gears - if you don't mind stopping and getting your fingers oily with the upshift - but the big ring's main purpose is to stop the fold from rattling (achieved by the plastic trouser guard on the stock crankset) and to avoid Doing A Pippa in normal trousers (I'll wipe the outer ring clean after using it on a serious ride). I figured it was marginally more useful to have a sprocket than a bash-ring.
I originally wanted an M-type, but after test-riding the S I decided it was infinitely superior
[1] handling-wise. I've stuck a Litepro bar extender on to achieve a bar height about halfway between the M and S type, while maintaining the S's slightly longer reach. This also means that proper luggage doesn't foul the brakes/cables. Ergon GP2 grips. The fold still works (even with all the gadgetry on the bars), though the bar-end may may only clear the ground because of the rack and easy wheels (can measure if anyone cares).
Dynamo lighting, because it's just *better* (especially on a bike that's going to do a lot of sitting around and then be ready to go at short notice). Shimano hub because the budget didn't stretch to the Schmidt, though I've replaced the Lyt B with a Cyo, because the Lyt has no standlight. Moon Comet battery light on the saddle rails, because two is one and one is none. The black Scotchlite is there as paint protection. I couldn't achieve a decent finish with that large an area of helicopter tape.
I've bodged the hinge clamps with a compression spring and bit of plastic box so they're self-opening and auto-aligning. I've no idea why Brompton haven't done something to improve them. I'm also wondering why they haven't discovered seatposts with alignment marks on them.
Wellgo QRD pedals, so I can swap between SPDs and flats, and to avoid folding pedal on non-Brompton crank issues.
I'm still waiting on the correct size bottom bracket (chainline's a few mm off), and I think the brake cables could be a centimetre or so shorter (I've moved the levers inwards to make room for the shifter since I replaced the stock cables to compensate for the change in bar height). And I'm not 100% convinced by the Brompton saddle, though it's a lot better than I expected it to be.
But yeah, I've got a a) bendy bike that b) goes up hills and c) is sufficently low geared to be used as a mobility aid
[2] next time I b0rk my knee.
Many thanks to the various People On The Internet who unknowingly provided useful input to this project, including - but not limited to - Arellcat, rogerzilla and velovoice OTP.
[1] The less said about the P-type the better. I suppose it must fit *someone*.
[2] A large part of the reason for getting one, other than the usual trains and security stuff. I don't see myself doing huge mileages on this (though I'll probably have to ride to Brighton at least once on principle), but having it available as an alternative to walking (in situations where a full-sized bike isn't really practical) should be extremely helpful.