Pet the pony! Go to the address bar of your Reddit window (not this one), delete everything there, type "javascript:" (with the colon, without quotes), then after that paste this (one line)

gistfile1.txt

(function(){var NPETS=3,MAXLEN=100,INTERVAL=100,POS_PROP='background-position',KARMA_POS='-0px -0px',DIS_POS='-55px -0px',$name=$('span.redditname a'),$img=$('#header-img'),initialName=$name.text(),initialAttrib=$img.parent().attr('title');$name.text('pet me please');$img.css(POS_PROP,DIS_POS);$img.parent().removeAttr('title');$img.mouseenter(function(){var buf=[];window.petkarmaint=setInterval(function(){var nmin=0,nmax=0,i=1,indownstroke=true,happy;buf.push(window.petkarmay);while(i<buf.length-1){if(buf[i-1]>buf[i]&&buf[i+1]>=buf[i]){nmin+=1;indownstroke=true;};if(buf[i-1]<buf[i]&&buf[i+1]<=buf[i]){nmax+=1;indownstroke=false;};i+=1;};if(nmin>=NPETS-1){window.petkarmahappy=true;$name.text('HAPPY! coded by btown_brony, vectors by Pinkie_Pi');$img.css(POS_PROP,KARMA_POS);};if(nmin<NPETS-1){window.petkarmahappy=false;$name.text(indownstroke?'pet':'...');$img.css(POS_PROP,DIS_POS);};},INTERVAL);}).mousemove(function(e){window.petkarmay=e.pageY;}).mouseleave(function(){if(window.petkarmaint){clearInterval(window.petkarmaint);window.petkarmaint=undefined;};if(!window.petkarmahappy){$name.text('you gave up...');};});})();