What does 'Nudge' actually do?

In Draw Something, if my opponent hasn't made a move in a little while (a day or so, I guess, haven't measured how long it takes) I get the option to Nudge them. The button is grey and appears where the green Play button usually is.

What does Nudging someone actually do? There are no kinds of push notifications that I can find to configure (at least on the Android version), and I've never seen an in-game message along the lines of "You've been nudged" or "Someone is getting really fed up with you".

So either nobody has ever nudged me, or else it doesn't really do a whole lot. Can anyone explain, preferably with images so we can see what being nudged looks like?

It re-sends the message saying there is a turn waiting to the person you have nudged.

You may have been nudged, but seeing as the message is the same as being sent a new game you wont have noticed anything different.