The Peppermill to Rule them All
This isn't just for black pepper—it can handle anything from cumin to cardamom, so it's worth having two or three for frequently used spices.
An Electric Spice Grinder
A Mortar and Pestle
Regional Spice Blends
Or you can always make your own custom spice blend to dole out as gifts. Try mixing equal parts kosher salt, turbinado sugar, ground coriander, and ground grains of paradise with two parts lime zest. It's awesome on red meat. And you can take all the credit for it.
Glass Storage Jars
A better bet is an assortment of glass jars (prices vary by size; $0.99 for four fluid ounces). They last forever, come in a range of sizes for those who buy in bulk, and allow you to see your spices easily (the lids can be labeled). I'd prefer an attractive set of glass in a cabinet to some flimsy wall-mounted tins any day. Your cluttered cook with four kinds of paprika will thank you.