I was just looking for updates on the playstation store, and saw this.
Monkey king costume, added on 16/04/09 (today)
It's from a `design a sackboy competition winner`
"This costume is the winning entry of a PlayStation Asia contest"
There is a link here to see what it looks likehttp://www.playfire.com/a/forum/littlebigplanet/thread/24983
Costume is in the latest section and the third one down :)
Not sure how long this is on the site for