Some news on regenerative shock absorbers:
Green Car Congress: ZF and start-up Levant Power partnering on first fully active, regenerative suspension for automobiles
These are a variation on what Levant Power has shown us in the past - the electric generator is attached to the top of the shock absorber:
Instead of just generate heat when your car travels over bumps in the road - you can get some energy "back" from that. A good thing, in my opinion.