Those of us old enough remember the NSU Ro80 as prematurely wearing out the rotor tips and lousy fuel economy. Thanks for reminding me about this fascinating engine (excellent piece in Wiki). Seems it might have an ideal future as a small light range extender for hybrids.

At present Mazda aren't selling (presumably not making either) any rotary engined car (the last being the '4-seater' [barely, at the cost of a lot of boot space] RX-8) at present, though a successor may be in the pipeline. It had a 1.3 ltr engine, developing between 200-240 bhp - the problems it suffered from were:

1. Low torque - you had to rev the proverbial nuts off it (even more than a VVTi type engine) to get all that power down, making it noisy like a vacuum cleaner - not a cruiser or an everyday car, more a weekend car for a thrash.
2. Very poor fuel economy and high CO2 emissions - see the HJ review.
3. Hates short journeys from cold (far more than diesels) which can ruin the engine, CAT etc in no time. Too many buyers were either ignorant of this (they didn't do their homework) or were duped by sellers, including I suspect the occasional main dealer.

Shame really it never took off - I personally liked the styling, both inside and out, it handled very well too. If they'd had made it a foot longer to get over 300 lts of boot space and ok-ish leg room in the back, plus either the V6 or better still the 2.3 turbo out of the 3 and 5's MPS models, they'd be on to a winner - it would've been near the top of my list.

As other said above, most of the major motor manufacturers experimented with rotary engines in the 60s and 70s, from Mercedes to Citroen to American manufacturers, to Suzuki, Yamaha and Norton/Villiers/Triumph.

The rotor tip sealing problems that plagued early designs were largely fixed, but the fuel crisis of the 70s and ever-tightening emissions regimes made it uneconomical for most makers to pursue rotary power further, apart from Mazda who stuck doggedly with it.

It's a pity because the design has advantages in that it spins smoothly, rather than thrusting pistons from standstill to standstill. But they burn oil, and are harder to meter fuel into.

Fixing the fundamental problems basically bankrupted NSU and nearly took Suzuki to the wall, too.