Give your plants a caffine boost with spent Ground Coffee. Well, so long as you apply it sensibly seems to be the consensus of opinion.
Don't apply as a thick mulch around your plants, rather use a thin layer and top off with bark or leaf mould. It is probably better to mix in with your compost heap and let it rot down alongside your grass cuttings and other plant materials. Like grass cuttings, too much spent coffee grounds can result in a gooey, slimy mess, so mix it up with stuff like shredded paper, news print, dried leaves and woodchip etc.
Some say it will discourage cats and slugs, others dispute this, I've no experience of this as yet but will keep an open mind. Where can you get spent coffee grounds? Some of the national coffee shops may have bags of spent grounds available for free to local gardeners, best thing to do would be to ask at your favourite shop.
