Yeah, like I stated to another poster just a moment ago, everyone has the refillable single-use K-Cup gizmo but very few people actually use the thing. It's just too much like filling up a bong load plus you have to rinse out all the messy coffee granules when you're done. Forget that.
We have some goofy lady at work who pre-packs a few of those single-use K-cup thingies in her dainty little lunch box to use in our Keurig machine and then washes it out down the sink in the breakroom at the end of the day. Makes me wince with the creepiness of it all, and I have a firm personal ethic of not doing anything suggestive of being the creepy fruity person in the workplace. I'd rather die than use the bathroom at work, for instance.
You can get those really adorable little white filters for the “K-Cup gizmo” and then the grounds go into the trash can where they belong. :-)