thanks for you answer very interesting

a bookmarklet is a javascript function which is within a bookmark, for example the one below will validates HTML using the W3C HTML validator :
javascript:(function(){ function fixFileUrl(u) { var windows,u; windows = (navigator.platform.indexOf("Win") != -1); /* chop off file:///, unescape each %hh, convert / to \ and | to : */ u = u.substr(windows ? 8 : 7); u = unescape(u); if(windows) { u = u.replace(/\//g,"\\"); u = u.replace(/\|/g,":"); } return u; } /* bookmarklet body */ var loc,fileloc; loc = document.location.href; if (loc.length > 9 && loc.substr(0,8)=="file:///") { fileloc = fixFileUrl(loc); if (prompt("Copy filename to clipboard, press enter, paste into validator form", fileloc) != null) { document.location.href = "http://validator.w3.org/file-upload.html" } } else document.location.href = "http://validator.w3.org/check?uri=" + escape(document.location.href); void(0); })();
it is stored as a bookmark/favorite in your browser, and i always wondered if one could launch a bookmarklet from FARR