<a href="msnim:chat?contact=xxx@hotmail.com"><img src="images/msnicon.gif" width="80" height="20" border="0"></a>
Skype:
<input type="image" onClick="location.href='callto://xxxx'" value="click" src="http://skype.tom.com/images/skypeme_btn_small_green.gif" alt="skype">
Yahoo Messager:
<a href="ymsgr:sendIM?username"><img border=0 src="http://opi.yahoo.com/online?u=username&m=g&t=2&l=cn"></a>
ICQ:
<a target=_blank href=http://wwp.icq.com/scripts/search.dll?to=你的ICQ号码><img border=0 align=absmiddle src=http://web.icq.com/whitepages/online?icq=你的ICQ号码&img=5 alt=ICQ在线状态 title=给我发送ICQ消息></a>