They call it sketch-dump

Some of these are old, some are recent.

The one on top is funny because I drew it during the most boring work meeting ever. Well ok, I think I also drew that trigger-looking fish at the same meeting... It was horrible

-_-

Bottom right: Arandaspida and Doriaspis, since it's hard to read.

Elka on top right

That floppy mutated rabbit-thing on top left reminds me of Mimiga's from Cave Story... hah.