[SauronOfMordor]

Modern Ainu seem like a cross between oriental and caucasian. Archeological evidence indicates that they were a fishing/hunting culture. It would not be too outlandish to think that a fishing culture would expand along the coastline of the Middle East, past south Asia, eventually hitting the Japanese Islands, and continuing on up the coast of asia and across to the west coast of North America

[blam]

The Hakka of China are an interesting group too.

I believe the Hakka are mixed blood descendents of these folks, The Curse Of The Red-Headed Mummy.
There are records of their migration all the way across China and the Hakka with curly hair or high nose-bridge were killed during this/these migrations. They are related to the 'red-headed' folks via than Han, Xiongnu, Miao, Yuezhi and ultimately the Schythians, all Indo-Asian steppe people.

[blam]

Sand-Covered Huns City Uncovered

[Cronos]

well, then you'd have to account for the fact that the S-E asians aren't Ainu, they are mostly Mongoloid with some Caucasian blood (courtesy migrations from Southern India).

However, there is the Tamil (South Indian) myth about the Dravidian peoples coming from an Island in South-East Asia that submerged around 7000 B.C. -- and the Tamil language has cousins that are found in coastal areas -- Brahui in Baluchistan (Western Pakistan / Eastern Iran), and supposedly, Harappan and Sumerian.

This is a point brought up by Blam before that I increasingly find to be true: it could be the source for the Ainu (some Dravidians moving east up to Japan) and accounts for the fact that India has two Caucasian branches (Aryan and Dravidian) with Dravidians being mostly in the Eastern coasts and up the Indus river and also for the fact that Sumerians seem quite distinct from their Semitic successors, the Akkadians / Amorites.