Spike Hoppin'

To earn infinite lives/skip levels, lose all of your lives, make no points, then hold down button 4 with your last life as you jump off a platform. You will then have infinite lives, and press button 1 to skip to a next level.

To view the Voyager flyby, hold down buttons 1, 2 and 4 on the GCE screen until Voyager appears.

Hold down buttons 1 and 3, then press 4 to access the hidden bonus game.