A caprese must-have: fior di bufala
Though at $14.99 for 7 oz, its price is a little eye-popping, if you haven't tried it, give buffalo mozzarella a shot this summer when those tomatoes start coming in and you're starting to want All-Caprese-All-The-Time.
If you haven't had it before, you'll really notice the difference. Buffalo mozzarella (water buffalo, that is) is silky in texture and tastes tangy, almost like a mild blue cheese. And it's delicate, making it a little wily to work with, ie slightly more difficult to make a cutting board to mouth swoop.
You can get the Francia brand shown here from the great folks over at France 44's cheese shop. You might want to call ahead though and make sure it's stocked. When I got mine, it was the last one.
Bonus: Buffalo mozz. is kosher for lactose-intolerant folks.