"VOCALO APPEND feat. 初音ミク" is a compilation album by FARM RECORDS. It contains 18 tracks, sung by Hatsune Miku, Kagamine Rin, Kagamine Len, Megurine Luka, GUMI, KAITO and Kaai Yuki.
A crossfade of the album can be seen on Nico Nico Douga and YouTube.
The official album website is available here.
The album is purchasable on Amazon.