This (edited) version (the original version is in the question) hides **your and other users'** user data **on all StackExchange** sites. 
   (I added the  *.stackexchange.com/)
It also blocks your own reputation and badges (which you can see at your profile page anyway).
   (I removed the last line.)

Special notes: 
You can easily add more websites to this list by editing.
Use tampermonkey to use userscripts in Chrome.


    // ==UserScript==
    // @name           Hide other users reputation
    // @namespace      CrazyJugglerDrummer
    // @description    hides all users reputations except yours in site header
    // @include        http://*.stackoverflow.com/*
    // @include        http://stackoverflow.com/*
    // @include        http://*.stackexchange.com/*
    // @include        http://superuser.com/*
    // @include        http://serverfault.com/*
    // @include        http://stackapps.com/*
    
    // ==/UserScript==
    function addGlobalStyle(css) {
        var head, style;
        head = document.getElementsByTagName('head')[0];
        if (!head) { return; }
        style = document.createElement('style');
        style.type = 'text/css';
        style.innerHTML = css;
        head.appendChild(style);
    }
    addGlobalStyle("span.reputation-score, span.badge1, span.badge2, span.badge3, span.badgecount, div.accept-answer-link, div.user-gravatar32 { display: none; }"); //hides undesired user info