to make something useful out of 'dead' batteries i've been building joule thief circuits. these circuits are very easy, cheap and fun to build plus it gives me a little bit less bad conscious when going to the recycling bin with the batteries. watch https://www.youtube.com/watch?v=K53beWYdIpc to learn more.
below are pictures of one variant. it has a small 3mm green led (salvaged from broken printer), a hand wound coil, a resistor and a transistor.
the batteries here came with my first ever (analogue) multimeter. they are 32 years old!. see the date code: 84-04. they still can drive the little led. amazing. i think running this little green led is a good way to use the last energy stored in these beautiful and truly long life batteries.