Here's a little snippet:
I recently created my own NES emulator. I did it mostly for fun and to learn about how the NES worked. I learned some interesting things, so I wrote this article to share. There is a lot of documentation already out there, so this is just meant to highlight some interesting tidbits. Warning: this will be very technical!
A lot of this might be obvious, but I found of it to be an interesting way of showing, in his own words, "...what people were able to accomplish with such constrained hardware."
If you're interesting in the emulator itself (and its source), you can grab it on GitHib. An interesting feature (which I haven't tried) is that this emulator can record animated GIFs.