Switching resolution on the PS3 isn't too complicated, but if you're trying to do it from memory on a TV that's blank because you've got the wrong settings it's nigh impossible. With the XCM E-SETER, you can quickly push one of the labeled buttons and switch quickly and instantly to the desired setting, bypassing all that Sony Cross Media Bar goodness their programmers worked so hard to port from the PSP. $29.99 is a bit too much if you rarely use this, but if you're taking your PS3 to your friends' houses to show off how great Heavenly Sword and Folklore are, you probably stopped reading and ordered this already. [Totalconsole]
Or, you could save your $30 and use the built in Resolution reset. Taken from the online manual:
"If the video output settings on the system do not match those of the cable or TV
in use, there may be no picture. If the screen goes blank, turn off the system.
Then, with only the system and the TV connected, touch the system's power
button for more than 5 seconds to turn the system back on. The video output
settings will automatically be reset to the standard resolution."
Jesus, people, read the manual!