Have you ever gone to a state of Unimaginable Blind Fury when...

[fenyx4]

Yup:

Pokemon Sapphire Cart 1 - lost it at a playground in elementary school
Pokemon Sapphire Cart 2 - lost it at a wedding reception
Pokemon Emerald save file - cart accidentally dislodged from GBA slot while saving for a Secret
Base battle

The Emerald one really pissed me off because it didn't do the "Save file has been corrupted. Previous save file will be loaded." event. It displayed "The save file will be erased due to corruption or damage." I tried doing Up+Select B; it froze again.I tried turning it off while saving in a new game, and then it recovered the file. It was like Emerald hated me. :'(

I think the "saving glitch" only applied to the Secret Base battles, but still...I lost 200+ hours on each of the carts+save file. :(
Altogether I lost 30+ Lv. 100 Pokemon (all legitimately trained from scratch), a few legit Shinies, a legit Jirachi, an AR'd Mew and Celebi (on the first cart), and a lot of good items...
I also lost the Johto starters my friend traded to me, so now I have to playthrough and complete the PokeDex three times... :(

Plus, I've noticed the "mysteriously deleted file" that gets recovered minutes later at least once...

Anyway, I haven't harmed anyone in my fury, but I do get depressed for a long while... This is why I don't let anyone mess with my Pokemon games, so the risk of deletion/ruining the game gets lowered, and if it does get deleted, no one else gets blamed. With this 'deletion' streak, I really hope I don't lose Platinum like this or get it deleted. In that case, PokeSav is a lifesaver for accidents!!! :D

 

[MiTjA]

One time, there were alot of people with children in our house, i forgot to hide my pokemon games and someone erased my sapphire file... When I found that out, I was really shocked, because I didn't know what was on it, as I transfered alot of pokes from game to game lately via RS box, so it could have been that all my EV'd lv100 pokes, shinies and EV'd legends would be erased. But luckily it turned out that only trash pokes were on it, including a rayquaza with useless nature/EVs. So after checking emerald and LG I had to lie down and breath for some minutes LOL

 

[ShadowWind]

unfortunately yes my little sister(she lieks pokemon) took my pearl the other day and trade my shiny adamant Lucario with perfect IVs and perfectly EV trained on the global trade center for a..... a...... a..... A DAM MANTYKE CAUSE SHE WANTED ONE you know when this happened just yesterday i haven't figured out a way too get her back yet but i will....oh yes i will.................

Signed by
-ShadowWind
-Jake
While in a fit of blind fury/rage

 

[Guillermo]

Oh yeah I remember one. I remember one time when I was babysitting this little 5 year old kid. His parents had gone out for a movie, I think it was.....Oh yeah it was the new mummy movie. Anyway this kid was just sitting there, watching me play my Pokemon Diamond version. Now by this moment in time after babysitting for...2 hours I decided to get a drink, keep in mind in Diamond I had just recently: Caught: Dialga, Giratina, Uxie, Azelf, Mesprit and Cresselia. All without saving, not once.
Beaten: E4....5 times.
So I went to get a drink, I got it, I came back and this kid had popped the game out of it's socket. So I lost Dialga, Giratina, Uxie, Azelf, Mesprit and Cresselia. I went mental.

 

[LethalTexture]

To be honest my save file has never been deleted. But I would be fairly miffed for a short amount of time. When you've spend 600+ hours breeding and training, it's understandable when all that time has been wasted. But then I'd realise that it's just a game and be forced to start over.

 

[Lynnx]

When my FireRed file was deleted (it wasn't me, the internal battery died,) with my LV 97 Charizard on it. I wasn't too angry/sad/traumatized though about losing that file, just the fact that it wouldn't save anymore.