I was marked as a donor until my health complications began to pile up. For the most part, I am not sure I'd have much to give. My lady parts are non-functional, I have a MVP in my heart, I smoked, I have kidney problems, bad eyes, etc, etc.
The last time I went to the BMV, I had it removed. Not because I'm hogging my organs, but mainly because they will not be worth anything to someone else. However, I've looked into several places to donate my organs for research (they like the tainted stuff).
I do have rare blood, I can't donate due to anemia - and I'm not sure how that goes when you die. But short of needing a detox from the medications I take, I'd think they could make use of my blood.
I kind of look at it like when I die, I really won't care what they do with my organs. As long as they keep me looking whole; I'm OK.

I worry more about making sure my family is cared for when I die than my organs. I really should think about it more, but I always seem to never do that.
Thanks for the reminder :P