Reddit reviews 12 Gourmet Coffees of Christmas Holiday Gift Set

Assuming they are not grinding themselves and just using the old Mr. Coffee, I'd get one of those "gourmet" flavored coffee gift sets. Most grocery stores sell these during the holidays. Here is an example

For ground grocery store coffee, Cafe Bustelo has a surprising amount of flavor.

Some specialty shops will pregrind coffee for you. Personally I like Starbucks and think their coffee is good if you're looking for something in between the grocery store and small time roasters. I've been drinking their Christmas blend since it came out this year and quite like it. It's a dark roast sumatra blend.

I recommend against getting something premium, especially whole bean, because a basic drip maker isn't really going to bring out the flavor of these beans and they probably won't be worth the added cost over just putting something like Cafe Bustelo in your maker.

However, Mistobox is a pretty good online vendor that sells gift subscriptions and carries coffee from a wide variety of specialty roasters. You can browse by roast and find a dark roast that you think will sound good to them.