Originally Posted by bostontrevor
Been done. The Sturmey-Archer ASC-3 was a 3-speed internally geared fixed gear hub (like the much more common AW-3 but fixed). I hear they're hard to find now. Personally, while it seems like a cool trick, it doesn't appeal to me. It's still a planetary gear which means quite a bit of mechanical inefficiency (relatively speaking) and besides, a large part of the zen of fixed gear is finding the gear that you can push under all or nearly all circumstances. For the zenness, it seems like a cheat to shift.
Actually, you can 'fix' an old Bendix two speed hub. See
here . As for the inefficiency, most internal gear hubs have one gear that is direct drive. Which means if you pick the right chainring and cog to make that gear your most used, you don't lose anything. As for the zen thing, different strokes for different folks. Maybe it's blasphemy for some, but for others it sounds like a great solution.