Many years ago I was working in the Netherlands for a global company and one global company we supported had a site in Yemen. They were running a two node cluster in Yemen that was supposed to be fully replicated as the site was connected via Satellite over a 128kb link. Of course it wasn't properly clustered and one node held the master configuration that hadn't been replicated to the other.
That node had a harddisk failure and was completely lost. The backup software also depends on getting to the master config so there was no way to restore locally or recover as the core metadata was required to bring everything back and this situation was never catered for.
So I had to talk through on a conference with the tech in Belgium who worked for my client and his onsite engineers in Yemen to take a backup of the metadata of the cluster, transfer it from Yemen back to Belgium, and then back to me in the Netherlands. I had to hand-re-stitch the metadata back together using a database editing tool I only learnt 3 weeks beforehand and then email back to Belgium and back to Yemen. Then I had to talk the onsite engineers the exact steps to take to restore the metadata.
The best part was that the onsite techs in Yemen would need to go for prayers every hour or so for 5 mins, so they would say "sorry, can't do that right now need to go for prayers, back soon" and if you can imagine when talking through people key stroke by key stroke as doing the incorrect step could completely destroy everything with lots of non-native English speakers was interesting. My manager was investigating flights to Yemen half way through the call as we thought the whole system was toasted.
Got it all back up and running on the first attempt as I had fully tested the complete restore procedure twice before I sent it all back.
Then I also have a USB disk that has a spinning disk inside in the days before USB storage. It developed a bad sector in the disk so now I have data on there I can't get off as the partition table was stuffed up and one day I hoped to be able to image the whole disk and get it back.