Another vote for charity. That way if she has a change of heart and asks for it back, she can’t have it and you come off as looking pretty indifferent to the callousness of the action. “Yeah, I was so hurt that instead of having some sort of angry ritualistic cleansing involving destruction, I engaged in an act of charity.”
Hey! You better get a good price… 
I second Grits and Hard Toast’s method (if you have the storage space). There have been times when I’ve decided a relationship is over. I’ll take everything that she had given me, reminded me of her, etc. and dump it in a box. Take the box and put it in the attic, back of a closet, whatever. As long as you don’t see it without ‘digging’ for it.
Later on when the scars are healed and the pain is less, you’ll run across that box. Maybe I’m just strange but years later I’ve found things that I want to keep, while at the time I wouldn’t have cared if it was destroyed.
Take whatever you get, don’t open it, and ‘hide’ it somewhere. I would think that the more thought you put into this, the more emotion you invest in this, the longer it’s going to take to put her out of your mind and out of your life. YMMV
If there’s good stuff you can sell, I’d advise that, give away what you can’t sell but is still usable; and do whatever you want with stuff too personal to sell or give away- store it away as a kinda time capsule of your life or destroy it.
Don’t just trash stuff other people could happily use though.
Well you could still give to charity or sell on Ebay the unopened box you receive from the ex. Just explain to the Good Will why it isn’t opened yet, or use the fact as a sellin gpoint on Ebay.
I wouldn’t recoment Ebay myself, and would recomend going to a distant Good Will store.
Well, I do have a crawlspace in my new apartment that has a whole bunch of stuff that I’m not planning to look at until I move in July. So I suppose I could toss it in the back and forget it until then.
But I really would like to have it gone, because, as those of you who have followed this soap opera from the beginning know, she will likely call or e-mail or IM sometime this week. I’ll ignore it, of course (I hope), but if she has sent it, she may want it back, and I’d love to be able to tell her I can’t do that.