Bookmarklet to add inline full-size images to Reddit.

gistfile1.js

javascript: (function () {
    var things = document.querySelectorAll("div.thing");
    for (var j = things.length - 1; j > 0; j--) {
        var thing = things[j],
            entry = thing.querySelectorAll("div.entry")[0],
            thumb = thing.querySelectorAll("a.thumbnail")[0],
            img = new Image;
        img.style.display = 'block';
        if (thumb) {
            var href = thumb.href;
            if (/\.(png|gif|jpe?g)$/i.test(href)) img.src = href;
            else if (/imgur\.com/i.test(href) && !/\/a\//.test(href)) {
                var id = /\w+?$/.exec(href)[0];
                img.src = "http://i.imgur.com/" + id + ".jpg";
            }
            if (img.src) entry.appendChild(img);
            img.onload = function() {
                var ho = this.height;
                var wo = this.width;
                var hn = 800, wn = 800;
                if (ho <= 800 && wo <= 800) return;
                if (ho > wo) {
                    wn = Math.round(hn * wo / ho);
                } else if (wo > ho) {
                    hn = Math.round(ho * wn / wo);
                }
                this.height = hn;
                this.width = wn;
            }
        }
    }
})();