Coffee is a passionate topic and a good cup of coffee fits right into living the good life aboard. here's my 2 cents on the topic:
We've landed on two methods we're happy with. Our french press works great. It's a thermal version so you can make the coffee and it'll stay warm in the pot.
Here's our Frieling french press
http://tinyurl.com/c3f59p
We've also discovered an easier way to clean up french press coffee grinds after you enjoy your brew. It's a little filter that after your done uses a small hook to pull the filter along with the grinds up. clean up was the only part I hated about the press. This certainly helps.
http://lifehacker.com/5648883/coffee-catcher-filters-and-simplifies-your-french-press-coffee
We also have a single cup Keurig personal mini on board which works great on AC or via inverter.
http://www.amazon.com/Keurig-35-Personal-Single-Serve-Brewing/dp/B001CTXWM6
The good thing about the mini is it has a pressure sensor that won't let you brew if you don't have a cup in it. It saved my hide a couple times already. We run it on a Xantrex inverter sometimes when out. But when at anchor we usually use the press since we can make many cups at once and I don't have to pull out an extension chord. Boiling water is quick and easy.
I say make a pot and enjoy. I'm heading down to the boat now and it'll be in the 40's in the morning. I'll certainly be enjoying a cup or two before changing the oil.