Instructions
Go to the "Settings" icon on the PS3 menu. Select "Network Settings," highlight "Media Server Connection" and select "Enable."
Open Windows Media Player, then click the "Stream" button. Click "More Streaming Options," then click the drop-down menu next to "Show devices On" and click "All Devices." Click the drop-down menu next to "Unknown Device," click "Allow," then click the "OK" button.
Go to the "Videos" icon on the PS3 menu. Select the name of the media server (the name of the laptop by default), then select "Video." A thumbnail list of all the videos on the Media Server will be displayed. Select the video you want to watch and press the "X" button to begin playback.