When i start my rx8 it has a obvious ticking noise....as well it is beggining to rattle from the back..i suspect the exhaust????

or maybe http://www.finishlineperformance.com/rx8/docs/damper_recall.html

beers

maybe the resonator hitting the heat shield.

I have a AT

and it makes these noises

The ticking is the injectors. You don't want to stop that ;) . The rattle could be the heatshield recall not done or the exhaust hitting the body. Have it checked out for that.

if it is only when moving, check your lug torque. a tsb has been issued for that also. 105ft lbs.

beers

my friends 8 makes a similar noise
its horrible sounds like the cat. but car has all recalls done.

I also remember reading that there is an auxiliary air pump that runs when the engine is first started to help bring the cat up to temperature. That could be part of the ticking you hear.