How did this not occur to me sooner? Take one of my favorite beverages, mix it with my other favorite beverage, add in some extra flavor and bit of time, and, well, the results speak for themselves.
Of course, there are coffee-flavored liqueurs out there. Kahlua is the most famous; it's based on rum, and tastes nice and sweet. But I like whiskey better than rum, and I want the complexity of a coffee liqueur, but not the inherent sweetness. By making your own, you can control quality of coffee, the amount of sugar, and the whole experience and overall flavor profile is totally a step up. And, it takes, like, five minutes.
For most men, cufflinks are one of those accessories that are seldomly used, but when you need 'em, you need 'em. You can buy custom cufflinks from anywhere between $20 to hundreds of dollars…or, you can make your own masculine, custom cufflinks for $5. This is an incredibly simple project that took about 25 minutes to make and, if I may say so myself, they look pretty great.