Mystery Tool

[Inno]

Can anyone identify this oddball item?

The white handle might be bakelite.  The little wheel spins around.  It does not have a sharpened edge.

[bill300d]

It's got that can opener look.

[Northwoods]

It might be that there was a seam gripper where that little hole is. 
You say the wheel is not sharp?  Maybe it used to be sharp?

[Inno]

Interesting thought about the seam ripper.  The rotating disc is not really sharp or sharpened, but it is beveled so that one edge is sharper.

Also, the little notch on the long part seems to have a cutting edge on one side. 

I'm attaching two more close-ups.  The second, empty, hole is identical to the one with the disc attached and is threaded, so maybe the disc can be switched over when needed.

There is a stamp on the disc with an asterisk and Maltese cross, plus "Rd1616".  I've tried to look up the patent no. but no luck.

[john k]

Am thinking can opener too,  seem to remember one that had two wheels, put on pressure, hold, then rotate the can with your other hand.  Early can opener designs were numerous as better mouse trap designs. 

[Catch22!]

I think it's whats left of a knife sharpener.  Here is one with a similar handle, but with more wheels.  The second one is not on a handle, but you can see how the two wheels would have been attached.  The notch matches also.

[Inno]

Knife sharpener it is!

Many thanks to all who helped!