normal_home = new Image();
normal_home.src = "images/nav_home.gif";

high_home = new Image();
high_home.src = "images/nav_home_hi.gif";

normal_about = new Image();
normal_about.src = "images/nav_about.gif";

high_about = new Image();
high_about.src = "images/nav_about_hi.gif";

normal_insur = new Image();
normal_insur.src = "images/nav_insur.gif";

high_insur = new Image();
high_insur.src = "images/nav_insur_hi.gif";

normal_why = new Image();
normal_why.src = "images/nav_why.gif";

high_why = new Image();
high_why.src = "images/nav_why_hi.gif";

normal_faq = new Image();
normal_faq.src = "images/nav_faq.gif";

high_faq = new Image();
high_faq.src = "images/nav_faq_hi.gif";

normal_blog = new Image();
normal_blog.src = "images/nav_blog.gif";

high_blog = new Image();
high_blog.src = "images/nav_blog_hi.gif";

normal_contact = new Image();
normal_contact.src = "images/nav_contact.gif";

high_contact = new Image();
high_contact.src = "images/nav_contact_hi.gif";

normal_business = new Image();
normal_business.src = "images/left_business.gif";

high_business = new Image();
high_business.src = "images/left_business_hi.gif";

normal_lifeinsur = new Image();
normal_lifeinsur.src = "images/left_life.gif";

high_lifeinsur = new Image();
high_lifeinsur.src = "images/left_life_hi.gif";

normal_homeprop = new Image();
normal_homeprop.src = "images/left_home.gif";

high_homeprop = new Image();
high_homeprop.src = "images/left_home_hi.gif";

normal_carinsur = new Image();
normal_carinsur.src = "images/left_car.gif";

high_carinsur = new Image();
high_carinsur.src = "images/left_car_hi.gif";


<!-- repeat the 4 lines above for any subsequent images. -->

function swap(){
if (document.images){
for (var x=0;
x<swap.arguments.length;
x+=2) {
document[swap.arguments[x]].src = eval(swap.arguments[x+1] + ".src");
}
}
}