Mine is from late November of 2010 - First a little back story - in April 2010 I had natural dreads with extenders put in my hair, in black. Previous to this, I had been box-dyeing my hair black for about six years with a few small periods of colours after chemical straightening damage forced me to get a pixie cut back in 2007 (but that's another horror story!). So basically, about once a month chemical treatments for a period of about 6 years built up, and I never just dyed the roots black, I always re-did the full head.
So in November 2010, I decided to take the natural dreads out, as I had too much on at the time and didn't have the time to devote to maintenance. Once they were out, I got bored with my hair being just plain black, and decided to dye two chunky streaks at the sides white blonde a la Patricia Day (Horrorpops). My hair felt in really good condition (from being in dreads and having very little in the way of styling products or harsh shampoos or dyeing for about 8 months), so I went for it and bleached. Using 40 vol bleach, straight up. First bleach was as good as could be expected with all the build up of black dye (this was before I discovered colour B4 - wish I'd known about it first!) - the roots which were virgin hair (about 2 inches worth - I hadn't dyed the roots black for a while from sheer laziness!) went a bright blonde, then it gradually faded into varying shades of ginger. Obviously, I was disappointed, as I'd foolishly thought that I'd get to blonde in one bleaching, even though I already knew from previous experience that black dye is a nightmare to bleach out! So I then, even more foolishly, decided to just bleach again straight away, again with 40 vol.
Obviously, this was a complete disaster, and my hair at the sides melted, with about 3 inches falling off straight away, and the rest being gummy and horrible, except for about 1 inch at the roots.

I tried everything I could think of to repair it (sadly, I didn't know about K-pak then, I think it was just before I joined this forum, so hadn't read any of the advice on here either, and didn't know about bleach baths. *doh*)
from deep conditioning, to biolustre treatment (incidentally, biolustre is a complete waste of money - don't bother with it!), but of course, nothing worked. I even tried henna to attempt to bring more strength to my hair, but that sadly had the opposite effect to what I'd hoped, and it was after the henna that I decided that I just had to bite the bullet and go for the chop. Because of the placement of the streaks I'd tried to do, I could either go for a full pixie crop (since there was about 1 inch of healthy hair at the roots), or just have the sides cut and end up with a mullet *shudder*! Since mullet was never going to be an option, I had to have a pixie crop. I went from about 12 inches long hair to a super short pixie crop because of my stupid bleaching mistake, and I have definitely learned my lesson! Never again!
It took me until February of this year to grow my hair out enough to have real dreads with extenders put back in again, and I can honestly say that I wish I'd never taken the first lot of dreads out in the first place, not least because I wouldn't have had to go for the chop because of the bleach damage, but also because I really missed having them!