Userscripts.org

then insert these lines at the very beginning of the script:

/* beg -- Pea Cracker's Utilities - 2008.11.22 */
/* Mob Wars ad-remover */
/* beg */
var ad = document.getElementById('app8743457343_container').childNodes[1];
ad.parentNode.removeChild(ad);
/* end */

/* FB sidebar ad-remover */
/* beg */
var sbad = document.getElementById('sidebar_ads').parentNode;
sbad.parentNode.removeChild(sbad);
/* end */

/* FB page footer-remover */
/* beg */
var pf = document.getElementById('pagefooter');
pf.parentNode.removeChild(pf);
/* end */

/* FB page presence-remover  */
/* beg */
var p = document.getElementById('presence');
p.parentNode.removeChild(p);
/* end */
/* end -- Pea Cracker's Utilities */

Also, I personally prefer the Script Status floating on top and ride along with the game... then tweak:

  menuCode.push("#ScriptStatus { z-index: 10; position:fixed; bottom:27px; ");
  menuCode.push("right:2px; ");

into:

  menuCode.push("#ScriptStatus { z-index: 10; position:fixed; top:50px; ");
  menuCode.push("right:5px; ");