Here are random icons generated from the entries on my PGP/GPG keyring; i.e. I grep’d out the fingerprints, jumbled them a bit for privacy, and then gin’d up identicons and wavitars for them.
Meanwhile, here’s another scheme to gin up images from random numbers; in this case the numbers are slightly less than random, e.g. barcodes. Barcode Plantage. It would be fun to have one that was based on a tangle of string, or a knot. This fun hack wordle could be repurposed for this as well.