YMSN-06 Proto Sinanju
The Proto Sinanju was created by Anaheim Electronics to aid in development of the new NT-D System. The resulting data was used by Anaheim to complete the RX-0 Unicorn Gundam. In U.C. 0094, the Sinanju was stolen (disguised as a transfer) by the remnants of Neo Zeon, "The Sleeves", slightly modified and used as the personal machine of their leader, Full Frontal.
*The MSN-06 SInanju was awesome, but this proto version is equally awesome! Definitely worth considering a custom build for this guy. *
Image from A.E.Media (The image is a fanart, and not an official image)