Are there any companies that are doing interesting work in hardware?

Check out JITX (SC18), it's using AI to automate circuit design. They are using a relatively unknown Stanza language for their CAD system.

[1]https://news.ycombinator.com/item?id=17654865

[2]http://lbstanza.org/

Check out Oxide: https://oxide.computer

While the news seems to focuses on ML and RISC-V, there is a huge amount of *other* activity in the silicon space. With [Google working to improve the open source EDA tools + PDKs while also providing free manufacturing](https://opensource.googleblog.com/2022/05/Build%20Open%20Sil...) there are lots of opportunities.

The "new" FPGA companies like GowinSemi and RapidSilicon are also creating some pretty cool parts.

not sure how specific you are about "interesting work in hardware" but this is the first thing that came to mind for me:

https://www.span.io/

total rethink of the humble electric panel.

If this had been around when I solared up my house I would have definitely done it.... A little hard to see doing it on it's own...

Eridan: https://eridan.io is doing really cool stuff in the RF hardware space. Main focus is telecom and 5G but there are tons of wireless applications when you redefine the architecture of a transmitter and do it in GaN

We design custom silicon for doing molecular dynamics simulations for drug-discovery work: https://www.deshawresearch.com/technology.html

Defense

Working on software in defense sucked a fat one. The guys working hardware enjoyed it a lot more.

Silicon Catalyst is a global venture incubator with many hardware projects in progress.

ASML