Let it snow

snow.js

javascript:%20(function(){var%20el=document.createElement('div'),b=document.getElementsByTagName('body')[0];otherlib=false,msg='';el.style.position='fixed';el.style.height='32px';el.style.width='220px';el.style.marginLeft='-110px';el.style.top='0';el.style.left='50%';el.style.padding='5px%2010px';el.style.zIndex=1001;el.style.fontSize='12px';el.style.color='#222';el.style.backgroundColor='#f99';if(typeof%20jQuery!='undefined'){msg='This%20page%20already%20using%20jQuery%20v'+jQuery.fn.jquery;return%20showMsg();}else%20if(typeof%20$=='function'){otherlib=true;}%20function%20getScript(url,success){var%20script=document.createElement('script');script.src=url;var%20head=document.getElementsByTagName('head')[0],done=false;script.onload=script.onreadystatechange=function(){if(!done&&(!this.readyState||this.readyState=='loaded'||this.readyState=='complete')){done=true;success();script.onload=script.onreadystatechange=null;head.removeChild(script);}};head.appendChild(script);}%20getScript('https://ajax.googleapis.com/ajax/libs/jquery/1.7.0/jquery.min.js',function(){if(typeof%20jQuery=='undefined'){msg='Sorry,%20but%20jQuery%20wasn\'t%20able%20to%20load';}else{msg='This%20page%20is%20now%20jQuerified%20with%20v'+jQuery.fn.jquery;if(otherlib){msg+='%20and%20noConflict().%20Use%20$jq(),%20not%20$().';}}%20return%20showMsg();});function%20showMsg(){(function(){jQuery.ajax({url:"https://raw.github.com/loktar00/JQuery-Snowfall/master/snowfall.min.jquery.js",type:"get",dataType:"script",success:function(){jQuery(document).snowfall({flakeCount:200,minSize:3,maxSize:6,round:true,shadow:true});}})}());window.setTimeout(function(){if(typeof%20jQuery=='undefined'){b.removeChild(el);}else{jQuery(el).fadeOut('slow',function(){jQuery(this).remove();});if(otherlib){$jq=jQuery.noConflict();}}},2500);}})();

Sources

jQuerify:
http://www.learningjquery.com/2009/04/better-stronger-safer-jquerify-bookmarklet

jQuery Snowfall:
http://www.somethinghitme.com/2011/10/05/jquery-snowfall-1-5-update-now-with-snow-buildup/