Taped a KeySmart SmartCard AirTag to the back of my laptop a year ago or so. Chargeable with wireless Qi charger, they claim 11 months of battery time. My iPhone should really notify me when an AirTag is running out of battery, I don't think it does. Cahomo Self Adhesive Nylon Patches from Amazon.se (actually I had to get the light gray from Amazon.co.uk). Thank you Amazon.com for moving into Sweden in 2020, it meant a lot to me and still does. Laptop is ASUS UX5304MA (1 kg), best I've ever had. See the section above (2026-08-26) for my geek installation.