Do you have a garden lyn ? If so coffee grounds can go straight on the borders in your garden, or in pots, to make instant compost. Also ideal at deterring slugs from your plants and roses are supposed to benefit from it as a top dressing. .
Great answer shaneystar2 - do you know if it works in reverse? ie. will slugs in the sink stop my husband from lobbing his coffee grounds in there and then not rinsing them out? Any tips for a good use of used up husbands would be greatly appreciated.