NonNFA ... that's no fun!
I would like to try a 32 cal revolver. I don't think I've even seen one down here in SouthFla.
And probably one of the higher end rifles like a Blaser.
I've shot the Desert Eagle in 50 a couple of different times, and the first time it was alright. Not pleasant, not fun, but tolerable. But the second time, I must have not had a good grip, cause it was downright painful and drew blood on my palm. I have small hands, and it's just too much for me. The 357 is loud and obnoxious but it's a tame recoil. The 44 is as well.
I passed on firing the S&W 500 as it seemed that it would be a heck of a beast for me. Same goes for the 454, 460s, and such. I once fired a few of rounds from a lightweight 300 Win Mag. Not fun at all.
I have fired 50 BMG from one of the single-shot AR uppers. It was alright.
I'd like to try the M107 some time.
For NFA, you know, can't resist. I've crossed off a few, courtesy of Uncle Sugar - M16(A1, A2), GAU5, M4, M60, M240, M249, Mk19, M2, M203 and a Sterling that was in the armory in Iraq. I have a buddy (SOT, FFL 07) with quite the collection Uzi, MP5, FG34, FG42, Bren, M1919, Glocks, PPSH-41, PPS-43, and a couple others - I've gotten the opportunity to shoot most of them. At other times, a Kriss, Reising, Sig 550, MP5SD (loved that), Sten, AK47, Mac 10/11, and a few others.
Still on my NFA want to shoot list -- a Tommy Gun, M3 Grease gun, AR180, AC556, Skorpion and a P90.