^5

I'm jealous

Rough ceramic tile

Masturbating.

maybe a forensics application?

Like, what scenario?

And I mean real world scenario, not a CSI "The killer sent us a picture of a bloody wall, I've identified from blood drop spatters that the wall is made of a rare imported Italian plywood which is only used in one building in the city!" type scenario.

But for a (more) serious answer I'd say that particularly finicky artists would appreciate having this as reference.

I'm sure that if you can tell the fluid properties of blood on various surfaces you can probably glean things like the angle and velocity that the droplet landed on it, which may be useful for understanding a murder. I don't know though really. It's purdy.