I used to be proud to be able to hum the whole Final Fantasy VII soundtrack
Smooth McGroove does it again with this wonderful arrangement of Zelda II: The Adventure of Link's Temple/Palace Theme. This man is a bundle of talent and I can't wait to see his next new take on an old classic.
As a rule, YouTube personalities don't normally impress me in this manner, but I've enjoyed Smooth's takes on classic gaming tunes. Perhaps it'll brighten your day a bit as well.