  We present generic scaling laws relating spreading critical exponents and
avalanche exponents (in the sense of self-organized criticality) in general
systems with absorbing states. Using these scaling laws we present a collection
of the state-of-the-art exponents for directed percolation, dynamical
percolation and other universality classes. This collection of results should
help to elucidate the connections of self-organized criticality and systems
with absorbing states. In particular, some non-universality in avalanche
exponents is predicted for systems with many absorbing states.
