Off of Hwy 190 to the west of Death Valley you can camp pretty much anywhere the BLM signs allow. There are lots of 4X4 trails leading up to old mines (Borax, Salt, gold siver and..) plus other geologic features.
Look here for more info
http://www.blm.gov/ca/st/en/fo/ridgecrest/panamint.html
Inside of Death Valley a few of the campgrounds are nothing more than parking spots with tables and pit toilets which I would consider boondocking.
We've never stayed east of Death Valley but based on the terrain and remoteness I'm sure there will be BLM designated areas.