Drag link to bookmark bar to save as bookmark. (Or on firefox, right click on the link and choose 'Bookmark This Link') After bookmarked it, you can use jKeyMagic anywhere on the web by clicking on saved bookmark. Bookmarks are also work on iPad/iPhone/iPod Touch, you need to sync bookmarks via Safari.
These bookmarks will attach to all elements with tag TEXTAREA and INPUT. You can also try out by clicking one of the following links and see what it does.
Text Field: <- will attach only to text field
Password Field: <- won't attach
File Field: <- won't attach
Email Field (HTML5?): <- wont attach if email field is supported by browser