What's Flash piece from clearspring.com?

What's with the piece of Flash content at http://www.lds.org in the upper left corner?

Using Firefox 3.0.14 with FlashBlock add-on 1.5.11.2, I see that there's a small Flash piece with a tool-tip that says the URL is

//bin.clearspring.com/at/v/1/button1.6.swf

One time, I clicked on the symbol to activate or play the Flash piece, but it did not appear to do anything.

That page is using the AddThis service (owned by Clearspring) to encourage people users to share content from that page. The file you referenced adds a Flash cookie that allows some kind of collection gathering.