  We show that two initially weakly coupled chaotic systems can achieve
self-organized synchronization by adaptively reducing their speed and/or
enhancing the coupling strength. Explicit adaptive algorithms for
speed-reduction and coupling-enhancement are provided. We apply these
algorithms to the self-organized synchronization of two coupled Lorenz systems.
It is found that after a long-time self-organized process, the two coupled
chaotic systems can achieve synchronization with almost minimum required
coupling-speed ratio.
