Naked at work: Sure, I’m unemployed. 
Given employment I’d probably still do it. Can I lie as to why I’m doing it? “It’s part of a country-wide protest to legalise public naturism. Haven’t you heard about it?” or perhaps “It’s part of our churches new practices - Once a year we celebrate the innocence of Adam and Eve in the garden of Eden”. After all, christians are a protected majority. 
Sweets: No way in hell. I have a huge sweet tooth.
Hardcore Porn Movie: Ouch. That’s a tough one. I think, probably not. But I’d have to think long and… err. Really carefully about that one.
…would you never again post to or read the SDMB?
Naked at work and no sweets? I’d do either for $100K. Do I win?
And, yes, I’d give up the SDMB for that, too… I’m new here, so it wouldn’t be THAT much of a wrench (though I would be sorry to leave).
I wouldn’t star in hard porn though. That’s too creepy even for me.
…Would you tell your spouse/life partner/significant other that you were cheating on him or her (even if you’re not), with no explanation and no excuse?
(This one’s easy for us singles!)
Assuming I get a “Get out of jail free” card along with that $1,000,000 (ooh, look at all those zeroes…), I’d definitely do it.
The one thing I figure I wouldn’t do for a mil is to become a vegan. Red meat and seafood is, after all, among the first things I would buy if I had a mil!
Anyone here willing to give up animal protein?
Oh, as for the others, I don’t think I could give up sweets, or meat. I’d try, but I don’t have the will power. I don’t know how well I’d do porno, either. My nerves would probably keep me from functioning, tho I’d try.
Well, if you meant the entire first floor of my building, I’m the only one there and practically nobody visits. So, yes.
If you mean the larger company complex, No freaking way.
I already get offers from people to see me naked for $ and turn them down, so no. 
But I’d give up sweets. I’m more a french-fry kind of girl myself.