We have already seen Google Chat support some cool emoticons. Facebook Chat does not seem to support emoticons at all though there is a hack that can be used to get access to practically unlimited number of smilies.
Facebook lets you share a thumbnail image of profile picture of users and fan pages by using [[xyz]].
So you can just enter then account id to share some cool emoticons with friends and relatives.
Reddit has a huge thread on massive number of accounts that can be used. Check it here.