Few platformers have had longer running series than Megaman.  Part of the reason for this longevity is Megaman’s Music.  A few examples:

Megaman succeeded at providing unique experiences for each level of the game.  Each of these examples helped by setting the mood for their perspective stages.  Megaman is one of the few games that I’ve actually listened to while not playing it (along with Cave Story, Katamari Damacy, and La Mulana).

I would also argue that Megman’s music has been highly influential.  You can look to the reviving chiptune genre for signs of this, but also to various remix projects and indie rock bands.  Take a moment and enjoy the old school music of this wonderful series.