  We study the synchronization of coupled dynamical systems on a variety of
networks. The dynamics is governed by a local nonlinear map or flow for each
node of the network and couplings connecting different nodes via the links of
the network. For small coupling strengths nodes show turbulent behavior but
form synchronized clusters as coupling increases. When nodes show synchronized
behaviour, we observe two interesting phenomena. First, there are some nodes of
the floating type that show intermittent behaviour between getting attached to
some clusters and evolving independently. Secondly, we identify two different
ways of cluster formation, namely self-organized clusters which have mostly
intra-cluster couplings and driven clusters which have mostly inter-cluster
couplings.
