var slideshow, slides, currentslide;
$(document).ready(function(){
 slideshow = $('div#slideshow');
 slides = $('img', slideshow);
 currentslide = 0;
 setInterval('advanceslide()', 3000);
});

function advanceslide(){
 if(currentslide +1 < slides.length){
   nextslide = currentslide+1;
 }else{
   nextslide = 0
 }
 $(slides[nextslide]).css('display', 'inline');
 $(slides[currentslide]).css('display', 'none');
 currentslide = nextslide;
}