In my ongoing quest to solve all of the world's problems
with fluorescence, I bring my latest contribution, it's pretty
simple.
So, plugging your phone charger into your phone in the
dark can be troublesome. This can easily be solved by
turning on the lights, however, easily woken girlfriends
also prove troublesome in this scenario. Instead, simply
incorporate a small UV/far blue LED, eg 405nm into the
end of the charger lead. On the phone, paint the inside of
the charger socket with fluorescent paint (pick a colour,
any colour).
The led on the charger should only light when you're
gripping it, via a sensitive momentary switch. Then, in
complete darkness, you will be able to easily locate the
socket on your phone.