My solution is a Tamron SP 90mm f/2.8 Adaptall-II (model 72B) which gives me 1:1 magnification and a comfortable working distance for just under £90.
Doesn't have the same reputation as the earlier 90mm f/2.5, so prices tend to stay low.
(Edit: some details here)
On my X-T1:
strawberry by Jean-Yves, on Flickr
greenongreen by Jean-Yves, on Flickr
I needed a low-profile lens hood for my X100T (so that it'd fit in a Black Rapid SnapR 35 without getting stuck):
hood by Jean-Yves, on Flickr
27-49mm step-up adapter stacked with a 49mm filter rim, reverse-mounted on the lens thread. Looks crap, works just fine; and I finally found a use for a UV filter.
Billingham 445. It'll swallow anything from a Ricoh GRD4 to a Mamiya RZ67 (with extra film backs and change of lens) with ease and and let me carry it in comfort and in any weather; looks good; and will probably outlive me.
I turned an old Leica neck strap (14312) into a couple of quick-release wrist straps:
Wrist Strap by Jean-Yves, on Flickr
The main benefit is having a strap which can be mounted or removed in seconds, and which doesn't leave anything attached to the camera when removed. Oddly enough, the only cameras I don't use these on are my Leicas (the strap lugs are brass and aren't guaranteed to support the weight on just one lug).
The 35mm f/1.4 by far; then the 56mm f/1.2 R just edges out the 18mm f/2.
Second-place usage may vary as time goes by, but I can't see anything ever usurping the 35mm's position.
It uses Instax Mini film packs.
It's a pity Fuji doesn't make a 'serious' camera for Instax film. I would love an Instax wide camera with a decent fast lens, accurate autofocus, and a competent metering/autoexposure system.
X-T1 (with 18mm f/2, 35mm f/1.4, 56mm f/1.2, and 55-200mm f/3.5-4.8; plus the Leica M adapter and a Nikon G speedbooster) and X100T, after moving away from Pentax (ending with a K5).
Fuji X is an astonishingly accomplished camera family.