Instructions
Storage
Connect the USB device to the USB ports on the front of the PS3.
Turn on the PS3. The first screen you see is called the XMB. From here, you can play games, use the Internet, or access your media.
Browse to "Settings" and hit "X" on "System Settings." Scroll to "Backup Utility" and hit "X." This will open the System Backup Utility, which you can use to transfer data from the PS3 hard drive to your removable media.
Back up the data currently on the hard drive to USB, restore previously backed-up data from USB, or delete the backup data.
Playing Media
Insert the USB device into the PS3's USB port and turn on the PS3.
Navigate the XMB to select the media you wish to access (video, audio or photo).
Hit the PS3's triangle key and select "Display all." The media you have stored on the USB will be visible. Hit "X" to play the selected the file.
Hit triangle during playback to access the PS3's media control menu, where you can turn subtitles on and off (if included with the media file), skip scenes, manage visualization (for audio files) and control slide show speed.