Replaces all text on a page with the font size. Useful for debugging the page or just replacing wretched content with something less awful.

bookmarklet-replaceTextWithFontSize

javascript:%28function%28%29%7Bvar%20n,walk=document.createTreeWalker%28document.body,NodeFilter.SHOW_TEXT,null,0%29%3Bwhile%28n=walk.nextNode%28%29%29%7Bif(n.textContent.trim%28%29.length>0)n.textContent=window.getComputedStyle(n.parentNode).fontSize%3B%7D%7D%29%28%29

replaceTextWithFontSize.js

(function() {
    var n,
        walk = document.createTreeWalker(document.body, NodeFilter.SHOW_TEXT, null, 0);
    while (n = walk.nextNode()) {
        if (n.textContent.trim().length > 0)
            n.textContent = window.getComputedStyle(n.parentNode).fontSize;
    }
})()