Which project did you invest in which is now dead?

Which project were you invested in which no longer exists or has fallen so far it might as well be considered dead? One in which your investment has dwindled so much and so close to zero, it's not worth the effort to sell and recoup what you have left?

I've invested in a lot of crap stocks over the years which went spectacularly wrong - went 'tits-up', so to speak, and are now effectively worthless; but during my short time in crypto I've more or less managed to avoid these types of investments (or at least jumped ship before the crashing and the burning began).

What project did you invest in which is now defunct, or effectively worthless?