How to stream from my mac to Ps3 or Xbox

Hi i am having troubles streaming videos from my imac (2008) to ps3, i have downloaded ps3 server from download.com but i have followed all instructions and my ps3 cannot find any media servers, neither does my mac find the ps3, is there any other software/apps out there that can help, or does any one have any suggestions?

Ps3 media server is turned on and all the devices are connected to the same network, so i dont see why this is difficult, also trying to do it with apple tv but cant figure that out either.