This paper has an interesting (but unproven) proposal for greedy forwarding in networks with power law degree distributions: for each neighbour of the current node, call its "greedy degree" the number of its neighbours that are closer to the target than the current node, and forward the message to the neighbour with the highest greedy degree.
http://www.rose-hulman.edu/mathjournal/2004/vol5-n2/paper7/v5n2-7pd.pdf Cheers, Michael
