- answered the door naked?
No
- done housework naked?
Yes, but rather few.
- been naked among dressed people?
Unfortunately no, but I'd love to do CFNM. It wouldn't even need to have contact involved..
- been naked among strangers?
Yes, at a nudist beach. 
- been seen naked on purpose, but made it look like an accident?
Yes
- skinny dipped?
Of course, in the night in the swimming pool with some girls. 
- posted a naked photo of yourself on the internet?
Yep
- spent more than 24 hours naked?
I don't think so...