Probably done before, sorry if I just didn't find it reasonably recently...
Just for fun, fee free to answer any or all... I feel kind of anal about numbering them, like a book report for English class, but it was visually easier to digest and gives ppl a quick way to say which one they're addressing.
1) What plant have you had for the longest amount of time that's currently still alive and how old?
On this I believe it's an Aglaonema that I can remember being in my room as a young teen, and the plain green spider plant that's been kicking around for decades may have come from the same planter.
2) If you previously had another plant that lived longer than any plants you have alive now, what was that and how old? OR what's the oldest plant you've killed?
Poor rubber tree, got to be so big and pretty, 8-9 years old, but unable to survive being stuck in a cold shed a few years ago.
3) What about a plant that you know is just really old but maybe you haven't had it for its' whole life?
Around 20 yrs ago my Gramma gave me a Drac. marginata 'tricolor' tree and some potted Sans trifasciata. Nobody remembers when the tree came into her life, but at least 35-40 years ago. My Mom's pretty sure the Sans is somewhere around 80.
4) The oldest captive plant you've seen?
When I lived in Columbus OH I liked to visit the Franklin Park Conservatory to see, among other things, their bonsai collection, some of which were tiny trees labeled as being 300, 350 years old. Although not unusual for a similar facility in any city to have such a collection, kind of hard to wrap your mind around standing there looking, reading the signs. Hard to imagine both the fact that such is possible AND that obviously a really long time ago, somebody had the idea to DO that and figured out how. How nervous do you think "the new guy" is at that job when a replacement is necessary?