I got some really interesting results PSTG-ing a square truncated file at about 1250 dpi. I'll post a series over the next several days. These look very carefully cropped and composed, but no final-stage cropping or other post-manipulation was involved.
Basically, I open a truncated file in an old version of PS, crop the black space to square (which for some reason preserves the truncation, keeping the image unstable), open a bunch of other files to fill up the PS cache, and then use Unsharp Mask (lowest settings of 1 - 0.1 - 0) to "freeze" the image. Then save off the ones I like as TIFF.
Undo. Repeat. Undo. Repeat.
The more you use "undo," the more previously glitched images are saved to cache. So the process yields interesting results only up to a point, when you start to see diminishing returns (i.e. images that are too recursive/entropic and don't differ much from one to the next).
Hope this makes sense. LP cover anyone?