Superrigidity in (exotic) buildings via Weyl groups

I would like to present an approach to proving some rigidity results in higher rank which was developed by U. Bader and A. Furman. It relies on Furstenberg's boundary theory and structural results for algebraic groups, and in particular their Weyl groups. Using these ideas, one can prove statements of the form "if this group G has a large (generalized) Weyl group, then any action on this class of spaces is elementary". I will give examples of such phenomena, and if time allows it, I will mention an ongoing project where "this space" is a (possibly exotic) affine building.