I use ballistol too - it is lighter than a lot of oils, has good 'creep' and spreads out nicely, and has antiseptic properties - it was even used as an emergency wound treatment in WW2. Funky smell, though!
A lot of old text books recommended oils that were prone to go off, like castor oil, olive oil, etc, but they said add a few drops of clove oil (another antiseptic agent) to prevent this.
A light mineral oil or sewing machine oil is fine. Just don't over-oil - when it gets into the pivot hole it gradually produces a black grunge which seeps out on the inside of the scales and along the tang.
Regards,
Neil