>>3949667>You might also look at OIympus PEN E-PL10. Lightest lens for that is probably the Panasonic Lumix G 14mm f/2.5 II Asph, at a combined weight of 435 g.Nevermind, Fujifilm X-A7 with the XF27mmF2.8 R WR is lighter at 404 g.
Best MFT seems to be the Lumix G100 at 400 g.
And lighter yet is the Sony α5000 and E 16mm F2.8 at 336 g.
Lightest interchangeable lens combo that I know of is pic related, the Sony QX1, which uses your phone as a display. With the above lens it weighs in at 283 g. Not sure if it's actually usable or just a gimmick.