Familand Converters!
These are used to play Famicom games on Nintendo,
or Nintendo games on Famicom. Break open a Gyromite or Exitebike cart.
Voila! There is a Famicom to Nintendo converter! Here are some pics of
a couple.
This is Micro Genius. It's the NES to Fam converter! 
The case broke off, but I didn't like it anyway ; )
Here's Fam to NES #1.
Great name. T89.
Here's Fam to NES #2. I like it better then #1. 
I've seen a couple of this kind.
If you have not heard of
this one, you must be new to this kind of thing.
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