I would like to present a relative simple approach to show uniform boundedness and a weak Harnack inequality for general hypoelliptic operators where ? ? a_{ij} ? ? is uniformly elliptic but merely measurable and the X_i are given smooth vectorfields. Furthermore we assume that they satisfy the Hörmander condition i.e. their Lie-Algebra spans R^{n+1}. The novelty is the avoidance of a "general" Sobolev embedding and a "quantitative" Poincare inequality. Somehow our approach shows that one can somehow consider even the classical De Giorgi-Nash-Moser theorem as a "perturbation" of the poisson equation. If time permits I would like to discuss as well how the geometry of the hypoelliptic equations come into play to obtain as a consequence the famous Hölder regularity.