For its time the Link Trainer was a revolution. Today's modern flight simulators are indispensable for training new generations of airline pilots, as well as lots of private instrument pilots. At home, some of us "fly" X-Plane or other software packages at our kitchen tables to get a feel for a particular approach, a cross country, etc. And all of these devices has an important role to play in flight training.
But, when it comes to inspired simulation, I would put Burt Rutan's solution to getting time in a single-seat type (the BD-5) up against any of them:
Not only does it sound like it worked well (including for crosswind landing practice), it sounds like a big ol' dollop of fun! There is a wonderful report on "flying" the BD-5 Trainer at airbum.com. I think we need to recreate this idea for everything from Citabrias to 767s. I volunteer to drive the truck!