The Send a Brick to Congress was pretty successful:

Leaders of the campaign, which has delivered an estimated 10,000 bricks since it began in April, said they had hit on the idea as a way to emphasize the benefits of a fence along the border with Mexico.

The Congress is trying to put the bricks to good use:

On Tuesday, representatives of the architect of the Capitol collected bricks from lawmakers’ offices and stacked them on loading docks with plans to donate them to a nonprofit group.
In a letter he circulated on Tuesday, Representative Scott Garrett, Republican of New Jersey, encouraged his colleagues to donate their bricks to a Habitat for Humanity resale store in Virginia, so the proceeds could go to that organization’s projects.
“Through the Send-a-Brick Project, our constituents have found a solid way to communicate their feelings about illegal immigration,” Mr. Garrett wrote in a draft of his letter. “Whether you agree with their message or not, we think that this campaign has given Capitol Hill a positive opportunity to turn bricks into buildings.”

Why not build a border fence with them? Save the taxpayers some money.