The sixth Finger based on Comic book story?
In the comic Superman's Pal, Jimmy Olsen #22
[b]http://dc.wikia.com/wiki/Superman%27s_Pal,_Jimmy_Olsen/Covers?file= Jimmy_Olsen_Vol_1_22.jpg
Prof Potter puts Jimmy under something that looked like a hair dryer and he too gets a giant brain like in the OL ep. Only years before same.
He sends Superman on some what looks like crazy tasks which as it turns out saves the world in years to come.
A later story had Superman with a giant brain but that turns out to be a hoax.
For me that was the first issue of Jimmy Olsen.
See some stars here
http://www.vbphoto.biz/