I just finished after many many years
Planescape: Torment
Wow this feels good.
I've had it for years, but never pushed forward to complete, one time when I was determined to complete it some stupid bug and not having a good savegame available caused me to stop from trying.
Last year I finally made a second attempt and stopped about 70 percent through and then just let it lie for a several months.
And now I finally finished it.
And it feels good. The feeling of having accomplished something epic (which it is, so I can heartily recommend it to anyone)
Oh and another thing which I finished (although this is only the first difficulty) is the wonderful
Median XL mod for diablo 2.
Anyone who likes diablo and a bit (or should I say loads and loads) of challenge and doesn't know what I'm talking about, should check it out immediately.