What are (good) references for results about iterated homotopy fixed points?  That is, suppose G is a topological group acting on a space (or spectrum) X, and H is a normal subgroup of G.  Then one would like to first compute the homotopy fixed points of X with respect to H, and use that as a stepping stone to compute the homotopy fixed points of X with respect to G.

(I am independently interested in both the space and spectrum versions, so am happy with pointers, comments regarding either.)