I used most all of them to fold into shirts, my favorite thing to do with paper I collect.
Here's a sampling of some:
I submitted my proposal to use them in a wall installation of 100 shirts, behind them will be a graph, filled in red for the percentage of unemployed people in the United States at the time of installation. Right now it's at 9% (and that's a drop).
With the remainder of the shirts I made a piece reflecting on the wastefulness of mailings and paper that gets recycled or even filed in office settings. It's a waste of time and space in my opinion... but for records it's necessary.