Haven't added anything to the list recently but came across this today. Ellsworth Moment frame. Sold over several years (early 2000s onwards) and generations of design, all appear to be Horst link designs.
My favourite suspension design, and one of the best still to this day.
Trying to rack my brain to remember some of the old school bikes, there were quite a few, Muddy Fox, mentioned above had a nice dh bike, the Ultimate, originaly in bright yellow, still have the catalogue somewhere...
A couple of of more modern bikes...
And only the later Intense M1's had the active design, the first version had the rear axle on the chainstay.