Sure, what the hell. It's very easy and is a big hit at the holidays.
First brew up some coffee real strong (like 5 scoops of ground coffee and fill the water to the 4 cup mark.) Let it cool.
Then mix in a blender:
2 eggs
1 cup half and half
1 can Eagle brand sweetened milk
1 cup Jameson's Irish whiskey
1/3 cup strong coffee, cooled
2 tablespoons Hershey syrup
1/4 cup creme de cacao
1/2 teaspoon real vanilla (use the good stuff- pure bourbon vanilla)
1/8 teaspoon coconut extract (no more, no less)
Blend for a long time, pour into a bottle, and chill.
When I make multiple batches for gifts, I buy Perrier water on sale and use the bottles for the Irish Cream.