I'm surprised that I never see my absolute favorite chiptune album on any best of list, but here goes:
Dong is a Japanese artist who released two albums that are incredibly refined, smooth and catchy: Gone Square and Go Square.
Gone Square in particular feels like a great video game soundtrack to a game that never was, but the songs are memorable and catchy on their own. It is the only chiptune album I've heard that not just evokes the era and uses it to create some nice music, but recreates *the feeling* of being in that 1980s/early-90s era - i.e., the feeling of genuinely new discovery. And they are genuinely well-written music, with great buildup, melody, rhythm, harmonies. I love every track off Gone Square and still listen to them over a decade after finding the album.
Go Square has some standout tracks and is a solid album, still one of my favorite, but a little rougher and hard to compare with Gone Square, just because that one is so good.
Gone Square: http://www.16dimensional.com/wp/?p=7
Go Square: http://www.16dimensional.com/wp/?p=6
All albums free to download, MP3/ZIP files.
His best other album is Omoide Overdose ( http://www.16dimensional.com/wp/?p=114 ), but he mostly stopped making music about 10 years ago and I think he never caught the same "something" as those two albums.