Prefuse 73 is great if you like glitch hop. Personally I would recommend One Word Extinguisher and Everything She Touched Turned Ampexian the most - Vocal Studies & Uprock Narrative and Extinguished Outtakes are okay but not as good in my opinion.
One Word Extinguisher full album:http://youtu.be/GHcHh6bzIRU
(note that samples don't really do ESTTA justice - the whole album is meant to flow without any interruptions)
For Japanese nu-jazz I recommend Nomak and Uyama Hiroto. Both are similar to Nujabes and both have done collaborations with him.
For Nomak, I recommend Dynamic Meditation (more hiphop based) and Muziq & Foto (more jazz based). Calm is okay but it only has a few instrumentals and I'm not fond of the rap lyrics that the rest of the songs have.
Dynamic Meditation preview:http://youtu.be/OLqC7K8z_fkPost too long. Click here to view the full text.