In higher order Fourier analysis, there are d-dimensional parallelopiped structures which can be viewed as a $2^d-1$-ary relation of the form "given all but one vertex of a parallelopiped as input, return the final vertex as output".  (Here "parallelopiped" should be interpreted in a suitably abstract sense, as a family of $2^d$-tuples obeying a certain number of axioms.)  This point of view is taken for instance in [this paper of Camarena and Szegedy][1], building on the  [earlier work of Host and Kra][2].  In the d=2 case, this ternary operation is essentially equivalent to an additive operation once one fixes an origin (in which case the ternary operation becomes $(x,y,z) \mapsto x-y+z$).  For d=3, these operations are governed by 2-step nilpotent groups, and more generally d-dimensional parallelopiped structures are governed by d-1-step nilpotent groups.

These parallelopiped structures can be viewed as the abstract foundation of the Gowers uniformity norms, and they also share some formal resemblance to cubic complexes, which are constructs that appear mostly in algebraic topology and are discussed for instance [here][3].  There is a simplicial version of the latter concept known as a [Kan complex][4], but I do not know the details of how they are used.


  [1]: http://arxiv.org/abs/1009.3825
  [2]: http://arxiv.org/abs/math/0606004
  [3]: http://www.ams.org/mathscinet-getitem?mr=2002612
  [4]: http://ncatlab.org/nlab/show/Kan+complex