Extracting content from Nes roms.

[Henko Waratenko]

So, is it possible, and if so, how?

[Toasty]

Sure, the ROM contains every image and sound to be used in the game. As for knowing where to look and how to interpret the data, that depends on the game. Check in the game modification section at Zophar's (http://www.zophar.net/utilities/mod.html) for some tools that might help you out.