And 淋しい熱帯魚 is a Wink cover...
(I don't suppose there's any chance that 卒業 is another ZONE cover -- there are about a million songs with that title...)
Vocaloid-style: Well, audio-editing software these days has very good frequency-shifting -- I imagine we'll be hearing Kikka singing all the way up in the Miku range.
(I did find a few interesting Miku covers of Secret Base on niconicodouga and YT, by the way
)
This one's pretty good, for what it is (with 初音ミク, 鏡音リン, and GUMI)...
[youtube]k5dNm43dlmo[/youtube]
The one vocaloid producer I'd like to see on that list (didn't see him there, though) is 現実逃避P/wowaka, who did Rollin' Girl and World's End Dancehall -- he might do some interesting things with the covers, at least...
If madness made us strong, we would all be invincible.