Background: As I was viewing this question, I felt it worth drawing the OP's attention to other posts discussing the potential dangers of trying to treat $\infty$ as a number when performing arithmetic operations. I recalled an answer of mine which addressed that issue directly. I sought said answer immediately for linking, only to discover that it no longer existed! I deduced (through sloppy reasoning, but I digress) that the question was deleted, and checking the OP's profile confirmed it. The question's loss was a bit frustrating, at a shallow level (a.k.a.: reputation and badge loss). At a more general level, I recall having linked to my answer there previously (and I think Alexander Gruber's, which was very nice), which means that at least one (possibly) extant post is now made weaker (or at least more confusing) by containing dead links (unless, of course, said links are automatically removed when the linked post was, to which I cannot speak).
Question: Ultimately, it occurred to me that, in many cases, beneficial answers could easily be removed from the site when a question is deleted, as long as the OP didn't accept any of them. Is it possible or desirable for a question to become a "Community question" to preserve its answers, if it is the OP who opts to delete the question? What if it is the M.SE community itself who votes for deletion? It seems that in the latter case, the baby should probably be thrown out with the bathwater, so to speak, though I'd appreciate input on both questions.
Added: Having further read up on (auto-)deletion (thanks, Martin), it seems that the question must have been deleted by vote or deleted by a moderator.
Added: It has been pointed out to me that I did not, in fact, lose reputation or badges when the question was deleted.