My Blackberry seems to love rebooting itself sometimes when I come onto the forum using my phone.
It also rarely reboots when I press any button on my phone and it really annoys me.
Most of the time if my battery's high, the phone would show "Battery too Low for Radio use" despite the phone isn't low on battery.

Has anyone ever come across this?

Probably worth reinstalling the operating system. Just connect it to a computer running the Blackberry desktop software (http://uk.blackberry.com/software/desktop.html)

Alternatively, get rid of it. Blackberry is a dying platform. I've been a huge BB fan and user for many years but the end is now in sight. Where I work, we are in the process of replacing around 1000 BB phones with HTC One handsets.

How is Blackberry a dying platform while it's still released on new devices and actively updated and maintained?