Selecting/marking/checking all checkboxes from a page

/* The code below is a bookmarklet for selecting (mark/check) all checkboxes of a page - a very useful feature. You can just copy the line below and paste it in the address bar. Also, you can make a bookmark from it. */
javascript:(function(){i=document.getElementsByTagName('input');for(k in i){j=i[k];if(j.type=="checkbox")j.checked=true}})();