I've actually just begun doing this. And I'm finding that it benefits the plants as well as me. There are less pest esp scales and mealies and I like it because the leaves are shinier (is that a word?).
I use a mix of Eco-carb and Eco-oil which are foliar fert and pesticide respectively. it is also suppose to be environmentally friendly and non-toxic (which is weird for a pesticide but ).
Oh and I do this regularly, like once a month so I've done it twice so far hehehe...