ANY Nikon DSLR bodies (10mp+) that take N/Ai Lenses w/o any modifications?

An interesting take but I would note two things:

 

First, watch out with a pre-AI lens, or one only partially converted to work on AI bodies, on a low end body whose minimum aperture tab is moved sideways rather than down. D40 60, and anything newer than a D3000 is OK, but not others, including the low end AF film bodies. [...]

Yes, thank you for that important caveat: it can be difficult to remember the various "gotchas" accruing as Nikon increasingly violates the spirit of its vaunted "backwards compatibility". If it was possible to edit my earlier post I would incorporate your warning about the sliding switch in bodies after the 3100 era. While I have heard of some adventurous non-AI lovers filing that switch away, I think it more practical to simply choose an appropriate body instead. At this point, there are enough second-hand model revisions to the 3000 and 5000 series that its fairly easy to find the combination of sensor and non-AI compatibility you desire. Later less-compatible bodies mostly enhanced features that work only with AFS lenses anyway: there's no particular advantage to using the 3300 instead of the the 3100 with non-AI lenses (in fact, the 3300 is a bit of a lemon all-around). My D40 has the nice retractable switch, so has no problem mounting non-AI lenses (the D700 omits the offending switch altogether, but has an AI coupling tab that gets in the way unless filed down).

Second, while grinding down the AI tab on the camera sounds like an ingenious way to get it to run pre-AI lenses, I'm guessing it would also bypass milled ring conversions, a small inconvenience if you have any lenses that are converted that way.

Yes, filing the AI coupling tab on the D700 would likely be an all-or-nothing proposition: you either want a dedicated full-feature full-frame body for your non-AI lenses, or you don't. At current used prices, dedicating a D700 to non-AI use is quite practical, esp if you have a half-dozen or more such lenses. It costs an average $40 per lens, plus shipping both ways, to have a proper full conversion done that includes milling in the EE post. If you'd rather not spend the money or alter the appearance of your non-AI lenses, altering the D700 to mount them is very appealing. The only thing you'd lose is open-aperture metering: you would need to stop the lens down to get accurate manual or aperture-priority exposure. Also the EXIF aperture data in your files would all indicate f/1.0. BUT: at least you do still HAVE metering, nice big viewfinder, triple < o > electronic focus aids. etc. And of course, you get the wonderful 12MP full-frame D700 sensor: in many ways still the best FX-size sensor available for manual Nikkors. The 16MP sensor in the D4 and Df is arguably better (at much higher cost). The 24 and 36 MP bodies are less forgiving and more prone to color issues with old manual Nikkors, the 46MP in the new D850 is amazingly good but very costly.

I just pulled out a couple non-AI and AI lenses to check the mount on my own D700. There is some variation among the non-AI lenses in depth of aperture ring: some, like the 28mm f/3.5, glide right over the AI tab and don't foul it at all. Others like the 50mm f/1.4SC and 135mm f/2.8QC press so hard against the tab they are impossible to mount. I did distractedly manage to get the 50mm mounted, but then had a scary moment or two when it refused to come off without a lot of coaxing. Comparing against the flange depth of my "genuine AI" Nikkors, it does appear there could be some wiggle room in how much material would need to be filed off the D700 AI tab. Looks like it should be possible to file it down to a compromise depth that would allow clearance for most non-AI lenses while still being able to fully couple with AI lenses. Perhaps somebody will try one day, and report back.