(If you thought this was completely useless/stupid, check out iPhone Doom)

nervegas's version of the emulator can be found at http://iphone.natetrue.com/nesapp/. It'd be nice if there was one central location, but...

A native NES emulator for the iPhone, currently using the InfoNES core.

Video of the emulator in action can be viewed at http://youtube.com/watch?v=LVh429Dp7r0

Many thanks to stepwhite, nervegas, nightwatch, bwhiteman, dshadow, wheat- and others.

Latest version is v0.31 available at http://iphonenes.googlecode.com/files/NES-0.31.zip

ChangeLog

Presently there is no sound sound, but requires killing mediaserverd.

And the control is a bit iffy (using an image of an actual controller, while cute, sucks).

ROMs need to be placed in /var/root/Media/ROMs/NES

First screen listing the available ROMs:

Clicking on a ROM (so long as it's a valid ROM w/iNES header) takes you to the second screen, the emulator itself:

And for the landscape view:

(Screenshots thanks to Erica Sadun's iPhone Screenshot Utility)

And many thanks to the #iphone-dev people, without whom none of this would be possible.