A completely open source laptop by MNT Research GmbH. Its motherboard is built to accept custom system-on-module boards that allow upgrading the device without replacing everything else. It also uses standard 18650-form battery cells instead of pouches, and has a mechanical keyboard using low-profile Choc switches. Optionally comes with a trackball (my own preference) instead of a trackpad.
Notably there is no lid switch, no webcam, and no microphone. MNT Research does sell an open source webcam as well, which was developed after the release of the Reform.
Rather thick, with a solid aluminum chassis. There is currently a smaller (but no thinner) "Pocket" variant available, and a thinner "Next" variant in the works.
I've been using one as my primary computing device for a couple years now. If you're the tinkering type, they can be quite fun.
With the RK3588 module installed, it draws around 9 watts.
I wasn't getting good wifi reception in some parts of my house initially, so I replaced the stock antenna with a pair of 8dBi wifi antennas, and designed 3D-printed rabbit ear-style mounts for them.
After I had a kid, he wound up tearing one of the ears clean off, along with the antenna panel, so I designed low profile antenna mounts that fit under the keyboard ledge, which is what I've been using to this day.
Both were designed in OpenSCAD, and the source for the mods is up on Codeberg.
I'd previously tried a bit of a hack using overlayfs to keep any additions over a stock Debian install separated, but that caused enough issues around upgrades that I'm now just running stock Debian, with /boot on my SD card and everything else on my NVMe drive.