Put this code in your browser address bar and hit enter:

javascript:void(function(w){try{_gaq._getAsyncTracker()._setVar(w)}catch(e){try{__utmSetVar(w)}catch(e){pageTracker._setVar(w)}}alert(w)}('your_keyword'));void(0);

Don’t forget to set the your_keyword as your unique word in Google Analytics filter settings (Cookie method of course).

…and to test if the cookie is set in the browser:

javascript:alert((/__utmv=.+?.(.*?)(;|$)/.test(''+document.cookie))?RegExp.$1:'No unique word');void(0);

Note: Modern browsers will strip-off the javascript part, please use Inspect element on Google Chrome or Developer Mode in Firefox.

Still won’t work? It does for me, at least, so far. Post here, I’m working to find a full-proof method, especially after GA updated with new set of codes.