For a strange melting screen, hold L1 + R1 + Up-Left + Triangle + Circle + Start + Select. You'll hear a grinding noise. Release everything and hold L2 + R1 + X + Triangle + Down. You'll hear a spoken word if you did this right.
Once this code is activated you can skip a level at any time. To do so, press L1 + L2 + R1 + R2 at any time. You'll warp to the next level as soon as there are no enemies on the web.