AMD is advanced towards being the first to market with HBM2 on a consumer graphics card with the upcoming Radeon RX Vega, placing the VRAM onto the interposer, along with the GPU die. It's an incredible feat, and a big change from the spread of DRAM chips around the GPU, using precious PCB space. Well, researchers at Stanford and MIT are doing one better: putting the CPU and RAM onto a single unit.
The researchers have teased a prototype processor that is made from graphene carbon nanotubes, with resistive RAM (RRAM) layered on top. The team says that their prototype chip is "the most complex nanoelectronic system ever made with emerging nanotechnologies", creating a 3D computer architecture. Carbon is the key here, as the use of silicon for the CPU isn't good for the high temperatures required, as the RRAM cells would be damaged.
I'm sure you're not surprised to hear that DARPA and NSF are funding the project, with the carbon nanotube sensors also able to detect gases, because the information can be processed and measured on-chip.