At the beginning of the game, when Aryll gives you the telescope, press A and left just as she gives it to you. This should cause you to roll to the left. Link will then hold up the telescope twice and you'll see a weird double-telescope! After the talking has finished, Link will have a telescope floating above his head until you enter a door or die! The telescope will also leave a 'trail' of shininess whenever Link runs about. It's quite tricky to pull this off. A better way is to use the Gameshark Moonjump code, and moonjump just after Link holds the telescope up.
Submitted by: Thomas Pitt