The little Meshtastic node inside of my ThinkPad T420s is surprisingly good (one of the antennas measured quite well for the frequencies used, so I wired it in. I assume it was meant for GNSS? Or UMTS?).
The PCB is a quick custom design I whipped up in EasyEDA to connect an ESP32-S3 with an SX1262 radio chip. It uses the USB pins of the MiniPCIe slot originally intended for a WWAN modem in this laptop :3
Photo of the screen of the same T420s showing the meshtastic client open connected to the Meshtastic node via serial over USB
Inside photo of the bottom compartment of a ThinkPad T420s showing a custom purple PCB holding an ESP32-S3 and an SX1262 radio in the slot originally meant for a WWAN card.