Load up the page on an unsuspecting computer, enter a URL to redirect to, set up a page disguise and you're ready to go. The page will wait, showing the disguise page, title and favicon, until triggered.
Remotely trigger any waiting computers from another device (maybe your phone?) from afar. Trigger awkward songs and movies on multiple computers simultaneously, and watch from a distance as people look with confused faces. For full disguising, change the URL without navigating.