Which smiley picker button is the best?

What kind of Icon or Button should I add beside the Send button at the bottom right of this design as a trigger to open a Graphical Smiley selector popup? I'm considering something akin to the greyscale graphic used in iChat and Yahoo for Mac, but this looks somewhat strange beside the Send button. Perhaps a square yellow button with a yellow smiley on it. What do you think?

Skitch is neat for making shiny looking thingo's

Maybe this is the logo for Legs?