I ran a BBS as a teenager and wish I kept a backup of it. I wrote it myself. The source code I could live without. But it would've been fun to see some of those crazy posts from the early 90's.

University project (a game) I wrote in Java (Java applet!). Not a big deal and not a great game but would love to see my bad old cold. (Or great code?)

A whole album

I lost a lot of my early computing history when I had everything on an external NTFS hard disk became corrupted. School projects, early Game Maker games I worked on, first music collection. The worst part is it was probably trivially recoverable with Photorec, but I had no idea that existed or how to use it at the time, so I just formatted the drive and went on with life. Wish I had left it alone!

In High School my friends and I made a movie that was the culmination of all our filmmaking talent and fun. It was about a guy who finds an old pair of leather pants that turns him into his ancestor, a viking, and that viking goes to school... Sounds dumb but it was truly hilarious in the late stage edits that I saw! The hard drive of that computer died during the final render and we weren't able to recover it. Tragic!

Multiple 100 megapixel images from Nunavut and Nunavik, Canada. I have the prints, just not the source. Bummer

I lost some DSP code I was working on (DOS, ca. '95). I wanted to recompile it, so I did something like 'del *.obj'. Or meant to. I typed 'del * obj' instead. Lost a day’s worth of work. (DOS even asked me if I was sure. “Of course I’m sure”, I thought as I mashed the Enter key.)

Result? I learned how to use make. (Borland had a nice one). I also started using my first VCS tool, sourcesafe (pre-Microsoft).

I had a hardware raid array, which in the middle of resilvering (with an XFS filesystem), suffered a power loss. It turned out that the initial drive failure was symptomatic of the impending power supply failure, and after replacement of the PSU, was unable to resume resilvering due to a corruption of filesystem metadata...

I carried the drives around in hopes of recovering the codebase for a virtualized+distributed SSI OS (Kerrighed-module-based), which had been in the works for about a year at that point.

Due to changes between 2.4/2.6 and 3.x kernel; the rise of user-level distributed computing in C/RIU, kubernetes+docker, I never really recovered the work: there were partial backups of some of the features scattered across three contributors' systems, but no coherent backup of the unifying components; and well "life" with one of the key contributors becoming 'Justice Impacted' stalled any real progress.

I use this as a personal motivation for RAID!=Backup.

My Dad worked for a small town and they needed a billing system for water and electricity in the early 90s. He learned C and wrote the entire billing system from scratch. It looked and worked amazing for a dos program of the time. After he passed away in 2021 they got new computers and ended up getting a new billing software and his software was never saved anywhere :(

My old Twitter account: posts/following/followers. Not long before Elon Musk took over the company, I was prompted for my age in the app. I decided to comply and got banned. Apparently I was less than 13 years old when I created the account, and they retroactively ban for that. Mind you there was no law in my jurisdiction about using social media at a young age, at the time. Still sad about that.

Several Bitcoin I had earned by mining as a stability test. I could have skipped the rat race and kept my soul... if only teenage-me wasn't astronomically stupid and unlucky

My Yahoo Mail since I was a kid.

Didn’t log in to it for some years and when I did it was all gone.

On one hand I’m kinda glad because I realized all this digital shit is just temporary.

Our human memories are forever.

I lost all my college projects due to source forge bullshit decades ago. And old pictures from digital/film cameras. Right now, I run both google/apple photos so I have 2 backups of my pics and videos.

Honestly, after 20 some years in technology, I don't think it's possible to back up everything unless you are willing to pay and constantly work at it.

Early in my career I was given the task of writing a simple code generator: read some simple strucured text file and write a file containing C++ classes with get and set methods. Pretty simple.

I worked on it all day, then tried running it - whereupon my choice of default output filename (main.cpp) caused it to overwrite its own source code. There were no backup copies.

I told no-one, stayed late to re-write it, and demo-ed it the next day. I like to think I learned some kind of lesson, but I'm not entirely sure what.