Styled dropcaps with CSS and JavaScript

dropcap.js

/*
A function to turn the first letter of the main article of your blog into a styled dropcap.
See example here: http://jamesabbottdd.com/articles
Change the id of the first article to reflect your markup:
var main_entry = document.getElementById("main-entry");
...and you're good to go.
*/
function addDropCap() {
    //separate the drop cap
    var main_entry = document.getElementById("main-entry");
    var paragraphs = main_entry.getElementsByTagName("p");
    var first_paragraph = main_entry.getElementsByTagName("p")[0];
    var text = first_paragraph.innerHTML;
    //some IE8 love
    if (typeof String.trim == "undefined") {
        String.prototype.trim = function() {
            return this.replace(/(^\s*)|(\s*$)/g, "");
        }
    }
    text = text.trim();
    var first_letter = text.substr(0,1) 
    text = text.slice(1);
    //create new DOM element
    var dropcap = document.createElement("span");
    dropcap.className = "dropcap";
    dropcap.innerHTML = first_letter
    var dcpar = document.createElement("p");
    dcpar.appendChild(dropcap);
    var t = document.createTextNode(text);
    dcpar.appendChild(t);
    //remove old, append new
    main_entry.removeChild(first_paragraph);
    var second_paragraph = paragraphs[0];
    main_entry.insertBefore(dcpar, second_paragraph);
}

function addLoadEvent(func) {
    var oldonload = window.onload;
    if (typeof window.onload != 'function') {
        window.onload = func;
    } else {
        window.onload = function() {
            oldonload();
            func();
        }
    }
}

addLoadEvent(addDropCap);