Simple Smileys is a free set collection of emoticons and smiley icons that are mono-colored, designed to work well alongside text. There are 45+ items where new ones are added within time, they are sized 15*15px and come in .PNG format, Adium Xtra, Pidgin Theme.
Simple Smileys is released into the Public Domain, meaning it is free (as in freedom) for any purpose.
Download : http://simplesmileys.org/
License : Free License