I have had a 'flexible' callus like lump of excess skin on the top of my left middle finger
, diameter being the size of an eraser of a regular #2 pencil. it is rough and hard, but moveable when felt. no fluid
or hardness underneath the callused part. i think i've had it since i had a pretty bad cut from a knife sharpening accident where i lopped of a good portion of the skin about 1cm. after it healed i'm pretty sure it appeared, and that was 1 year ago.