Hi Hoger.
The worst thing I find with these is when I am in the middle of something the damn battery dies & trying to find a battery in my house, especially when my kids have a habit of removing batteries from remotes to use for (substitute) their own devices thereby leaving me a near dead battery in my devices I think you get the picture. The first time this happened I thought my computer froze up so I restarted the system only to find that my mouse was still not working, only when I turned it over did I notice no red glow, dead battery, no spares so I had to hook up my old wired mouse.
The damn thing should beep like my smoke alarm does when the battery is getting flat.
Ben.