…is not wine. That seems absurd on its face, but makes sense when you think it through. A perfect gift is something that the recipient wouldn’t buy for herself or himself, but wine lovers buy wine all the time. Moreover, a great gift is always something really special, but buying a wine that will seem special to a wine lover is going to cost you a lot of money. Additionally, a perfect gift should also be lastingly enjoyable, but wine is generally gone after a single night. Of course, you could buy a wine that needs to be aged for years before it can be enjoyed, but 
that seems more like a test than a gift–like the slow-to-mature savings bonds that I used to get as a child from an eccentrically frugal uncle.
Spirits are actually a better choice. In my experience, the vast majority of wine lovers also really enjoy high-end spirits, but are generally too intent on exploring wine from the latest vintage or hottest new producer to buy themselves a terrific bottle of Scotch or Cognac.
Either of these can pass all of the tests that were just failed by wine: The recipient doesn’t likely buy them regularly; special bottles don’t cost all that much; the bottles are much more lasting than wine, and they can be enjoyed right away.
The world is full of wonderful spirits and digestifs like Bourbon and Eau de Vie and Armagnac, but I’d encourage you to focus on Scotch and Cognac because good examples are very complex (like great wine), competitively priced, and widely available.
Great gifts are attuned to the recipient, so think about whether the person whom you’ll be 
gifting might prefer a Scotch that is “intense and challenging” or “soft and soothing.” Choosing an intense and challenging Scotch whiskey couldn’t be easier: Laphroaig 10 Year-Old ($35 – $40), which is a thrill ride in a bottle driven by rich, smoky, peaty notes. If you’d like to buy something even better in this same style, Lagavulin 16 Year-Old ($65 – 70) is surpassingly intricate and enduringly interesting.
On the soft, smooth side, my pick at a more approachable price would be Glenmorangie 10 Year-Old ($35 – $40), a very satisfying Scotch that finishes with a subtle sweetness. A step up in this same style is The Glenrothes 1998, an unusual single “vintage” Scotch ($55), which is very complex but still very smooth in its overall impression.
For Cognac, if you’re looking for something fairly affordable and widely available, it is tough to beat Camus VSOP “Elegance” ($40 – $45), which offers a breadth of aroma and flavor that usually carries a much higher price. At a higher level, Delamain Cognac Grande Champagne “Pale & Dry” ($75 – $85) is marvelously nuanced in a relatively lean, restrained style, whereas Pierre Ferrand Cognac Grande Champagne Reserve ($80 – $90) is rich and full-bodied, with generous flavors, a rounded texture, and an exceptionally smooth finish.
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