I'd just go with the classic move-picture-around-on-a-photocopier trick. Google "photocopier distort" as that's basically what this is. I don't think it's really worth the effort of trying to fudge it in Photoshop when it's so fun and easy to do it properly. A computer scanner would also work but it'll never give the rough quality that an old black and white photocopier will though.
If you really want a Photoshop only method then Filter > Distort > Shear... is probably your best friend. You have to rotate the image to do it different directions.
I took my image from the newspaper photo thing yesterday (How to make scanned newspaper effect?) and messed around with the Shear tool and a little bit of the other distort options to make the following image. I also found Filter > Sharpen > Unsharp Mask... was nice to finish it off.
Here are a couple random variations:
Still no where near as good (or as fun) as doing it properly! I don't have a photocopier within reach of my bed though sorry!