One of the longest-serving computers I have kicking around is a shell server which since 1993(ish) has hosted my email, domain names, and websites.
Of course it’s been patched and reinstalled but I never bothered actually clearing the configurations up to remove old projects. Yesterday it suffered a bit of a meltdown and I took the initiative to finally do some tidying, a process which largely involved manually going through everything bit-by-bit, line-by-line.