Realistically, you can make ice pops in paper cups with wooden skewers for handles, but that's probably not as fun—or as trendy—as using a Zoku quick pop maker. Either way, it's certainly not nearly as fast.
The product comes in a range of sizes designed to make one, two, or three pops at a time; I tested the single quick pop maker ($25.99), but they all work the same way (and that way is pretty darn simple).
The ice pop maker goes into the freezer, just like an ice cream-maker bowl or those ice packs you stuff into your cooler. Then, when you're ready to make the ice pops, you just take the mold out, pour in your chosen liquid, insert a plastic stick from the kit, and wait.
It takes about five minutes for the liquid to freeze, depending on what exactly you're freezing and how many consecutive pops you've made in the mold. You can freeze up to three ice pops in a single mold before you need to shove it back into the freezer, and each one takes a little longer to freeze. Which is mainly to say that if you've got three kids, you might want to get the ice pop maker that freezes three at a time, because otherwise the last kid is going to be waiting for a long time.
As for what you can freeze, there are some limitations—plain water, for instance, will stick. Although why you'd use the Zoku for ice, I don't really know. The mixture needs to have the right consistency, but that still leaves you with plenty of options. My favorite was root beer—the carbonation affected the way it froze, leaving interesting streaks of color in the pops.
While this is no doubt marketed for families with kids, you can also freeze some adult beverages into ice pops, as long as the alcohol content isn't so high that it thwarts freezing. But at worst, you're scooping a slushy out of the ice pop maker. And let's be honest: that's not really so bad.
The instructions talk about customizing the ice pops with slices of fruit or even sucking out the center of the pop before it's completely frozen so that you can fill it with layers of different flavors. There are also add-on kits for customizing and decorating the pops. I'm not nearly that crafty, but it could be a lot of fun for kids (or more intrepid adults) to make their own special pops with fruit and juices.
Since this doesn't have any moving parts, it should last for quite a long time unless it's dropped or abused; it's not dishwasher safe. That said, there are replacement parts available if you happen to lose or damage the loose parts.
Disclaimer: Testing samples were provided to Serious Eats.