Under Pressure
It's time to take a little tangent away from the actual drinking part of this guide (for what it's worth I am sipping a whiskey as I write this) because I need to talk about ice. Now, this might seem dumb. It's ice. It's cold and wet. It keeps your drink from being warm and nasty. What is there to talk about?
I'm led to believe, quite a bit. Bartenders can be very picky about ice, because it does affect the end result. It melts. That water becomes the drink. You can see this, you're not dumb.
The picture above is fairly typical of the cubes you can expect to get from your standard home refrigerator's built-in ice maker or basic cube trays. They'll do in a pinch, of course, but they're about as far from ideal as you can get. Their small size and funny shape means they're going to melt pretty quickly and water down your drink.
On top of that, notice what color they are. These types of ice cubes tend to be more white than clear. That white color is actually a bunch of little tiny air bubbles that get trapped in there as the ice freezes. Now, this doesn't seem so bad... until you consider where that air is coming from. My friends, that air is the air in your stanky-ass freezer. If that air bubble is carrying any odor—and it almost certainly is—it's going to get released into your drink as the ice melts. You're over there trying to find the perfect gin-vermouth balance for your martini without realizing it's your sub-par ice throwing off the taste.
So what are our options? Well, they do manufacture ice makers for creating quality drinking ice. Most of these are big, restaurant-grade models, but if you're willing to drop a couple hundred bucks for the sake of ice, you can get a home model small enough to sit on a countertop. If you're like me though, counter space is a precious commodity, and it's a hard sell dedicating that space and money to making something you can already make in your freezer for free. Slightly-funny tasting drinks is a sacrifice you might be willing to make (like anybody can taste the difference anyway, right?)
I also saw a post online once where they filled a portable drink cooler (like the kind that hold sodas at parties) full of water and stuck it in an empty chest freezer until it turned to ice. It still wasn't perfectly clear though, so they had to chisel off the top half that got bubbly and then break the remaining ice into smaller pieces. I, uh, have a difficult time imagining that anybody is actually going to want to do that.
So let's talk about our most reasonable option: better ice molds! As far as bang for your buck goes, you can't beat an ice mold that put two seconds of thought into its design to get you nicer shapes and a cover to keep out that nasty freezer air. I've accrued a decent variety over the years, and I'll go over what I like and don't like about each of them.
A quick aside—I have seen molds that are supposedly designed in a way to get you "perfectly clear" ice. I haven't tried any; they tend to be pretty pricey and only give small yields. Also, who can say if they work as advertised. For the individual willing to half-ass it to get "good enough" results (and if you're reading this guide, that's you), it's okay to stick with something simpler.
Cube molds
Overall, these guys tend to be my favorite. They're no-nonsense and get good results. They're easy to fill and have lids to keep out that freezer air. The smaller ones on the left are more versatile; I'll use them for mixing in addition to cooling the drink. Mixing drinks really chews through ice though, especially when you're hosting, and I wish I'd gotten at least two of those.
The larger ones on the right have been my absolute go-tos in the past few months, although they don't fit in my shaker. Otherwise, great cubes. Not much to say about cube-shaped ice really. Let's get to the more interesting ones.
Sphere molds
I'm led to believe that sphere-shaped ice melts the slowest, so if you're particular about how watered-down your drink gets, you might want to consider one of these. In the above image, you can see I have two types: a single-sphere mold and a "tray" that makes four. Personally, I find filling the tray rather fiddly and time-consuming, and the ice balls are just slightly comically small, so nowadays I only use it when we have guests and I need as much good ice as I can get.
The single sphere mold kind of has the opposite problem; filling it is dead simple, but the ice sticks in the hard plastic bottom, so you have to run it under warm water for half a minute to loosen it and work the ball out. I guess in theory I could also let it sit on the counter for a few minutes before I poured my drink, but that would require forethought I do not have. Also, the larger size means it only really fits well in my short, wide rocks glasses, but it takes up so much space that some cocktails run the risk of overflowing. I mostly use these for drinking spirits straight. Honestly, if you have to choose between a cube mold and a sphere mold, go with the cubes.
Tiny cubes
Okay, so these guys are kinda fun. Basically, they exist to serve as an alternative to crushed ice when you can't be bothered to dig out the noisy blender. Personally, I love not digging out the noisy blender.
A couple of drawbacks on these though. First, I haven't seen any of these types of molds come with a lid. On the other hand, the kinds of drinks you generally use crushed ice for tend to be very sugary and fruity, so I feel like any stale air trapped in the ice is going to be overwhelmed by those flavors anyway. Second, these cubes are tricky to dig out of the mold (I usually can't get them all) and I have to empty them into a bowl before I can transfer them to a glass. Third, you're probably only getting one glass worth out of a full mold, so if you're planning on serving a lot of drinks it might be better to use the blender anyway. Still a nice option to have sometimes though.
Chilling rocks
Of course these aren't actually ice, but they serve a similar function and it seemed prudent to include them. If you haven't seen these before, they're cubes of stone or metal that you just store in the freezer and plop into a glass whenever, with the idea that they can chill your drink without watering it down. It's a good concept in theory, but in practice, I almost never use these. For one, I just don't think they do a great job of taking a room-temperature liquid and making it feel cold in the same way you get from actual ice. While cold water from melting ice will be integrated into the drink, the stones are simply absorbing the drink's warmth, which is never going to be near as effective.
For two, most cocktails are created under the assumption that they are going to be watered down by ice, and the ingredients are balanced around that. So I don't use them for cocktails. But even when I drink spirits straight, I generally like them watered-down a little bit to take the edge off (which is common. The whiskey highball—just whiskey, soda water, and ice—is a cocktail that thrives on this idea). The only use I've found for the chilling rocks is specifically when I'm drinking scotch, which in my mind just has too intricate a flavor to justify watering down. Your mileage may vary, but if you're not a whiskey-sipper, skip these.
Cat-shaped ice
Uh... so these were a recent gift from my mother-in-law. I guess I'm including them in the guide now.
They're cute, of course. And the tray is surprisingly less fiddly than the sphere tray I discussed earlier. And I suppose if you had some friends over and you wanted to delight them, this could do the job.
...It occurs to me in spite of my cynicism that you might enjoy the novelty too. I mean... they won't excel at anything, but ultimately they'll do the job sufficiently well. If you want cat ice, get cat ice I guess. L'chaim.