I recently went through my old floppy collection, and interestingly, the only disks with errors were the same few I recall having problems with 15+ years ago. I've simply kept them upright in floppy storage cases, away from temperature extremes, dust, and moisture (dry desert climate here). My old C64 floppies worked as of a few years ago... haven't cataloged those yet on safer media, so hopefully they still work when I get around to doing it.
