What's this thing inside my can of Guinness beer?

Factual Questions
1

To celebrate St. Patrick’s Day, last night I popped open a few tall cans of Guinness stout. Inside each can there was something white, hard, and too large to exit the hole on top. I took it to be a chunk of ice, which seemed odd because beer doesn’t normally freeze. Whatever, I was too drunk to care.

This morning, to my surprise, the white chunks remained rattling inside the cans. Intrigued, I cut open one can (very nearly maiming myself in the process, don’t try this at home kids!!) and what do I find but what appears to be a plastic ping-pong ball, with a few symmetric indentations along the seam. No writing of any kind (I expected it to say something like, “DESSICANT: DO NOT EAT”, but no.)

I checked out the can’s label but all I could find was this cryptic message:

**
Yeah, ok. I won’t argue with perfect pints. But my interest was piqued and I must know…what exactly IS this thing, and what does it DO??

J.E.T.

2

It’s the “widget”, found in “nitro-beers”. They’ve changed the design of these a few times. When they first came out and I dissected a can I found one that looks like a little gold-colored can, and a flat white plastic thingy. Boddington’s uses them too. Explanation:

3
4

A search would have revealed this thread to you.

Some retard spelled Guinness wrong in the title of that thread and again in the OP. Dumbass.

5

So, to summarize, it makes it foamy like when it comes from a tap.

6

And Cecil on the topic: http://www.straightdope.com/columns/000526.html

7

And here I was thinking this question would be too obscure for the SDMB folk…silly me, I should know better by now…

Lance, don’t be so hard on yourself, I thought it was one “N” too, right up until I wrote this post, when I looked at the can and saw it was TWO N’s…hey, you learn something every day, huh?

J.E.T.