Last week at E3 Siliconera.com had a casual chat with Brian Gerard and Frank O'Connor from Bungie. They started talking about Halo 3 and they are proud that it's on Famitsu's top 20 list. The Famitsu guys loved how the turrets can have a third person view. Soon the chat deviated from Halo 3's increased accessibility to their relationship with Team Ninja and later Halo DS. The short story is it may be real, but it isn't from Bungie.
S: I think I'm going to ask the forbidden question... was there ever Halo for the DS?
FO: I believe we got pitched for it several times.
BG: Every once in awhile it comes up. Somebody out there some developer pitches and tries to make it happen.
FO: Microsoft does publish DS games or licenses them, I think to THQ.
BG: It's very likely that somebody at some point in time created a prototype and tried to pitch it.
So there you have it! Halo does exist somewhere in miniature form...and it's calling your name, softly.