I recollect a SAS Fokker landing at the taxiway at BOO some years back. BOO, which doubles as RNoAF Bodø Main Air Station, is host to a squadron of F-16s, and apparently the taxiways are built big enough to function as secondary/emergency runway for fighters.

Luckily the taxiway was empty at the time. Pulling the same stunt at LHR during busy hours wouldn't have been equally sound.