Here's a tip you may not need. I will not rule out the possibility that I am the only bonehead in the world who has ever tried this, however, should there be more of you who are like me out there, learn from my mistake.

DO NOT add cocoa powder with your ground coffee to the filter of a drip coffee maker. You will be sorry when the steaming water hits the powder, causing it to form lumps of evil clogging nastiness and exploding in a steaming floe of wet coffee grounds all over your counter. The cocoa powder (or possibly the cocoa butter in the powder) clumps up at the nozzle which drips into the pot, clogging it completely. The water in the filter then backs up and over the lip of the coffee maker, making it look like your coffee pot is possessed when it spews grounds in a gurgling cascade of horrifying (though, admittedly yummy-smelling) near-boiling water. It takes a long time to clean up. If you want mocha in your coffee, do it on a cup-by-cup basis.

rootbeer277 says re Cocoa Powder: I suppose you could put the cocoa powder into the empty carafe, too.

preach on, brother...