Back in 2012, Loot Crate began offering geeks a way to get the kind of tchotchkes that come with videogame pre-orders minus the actual videogame, and since then the subscription box business has boomed. Now almost every niche interest you can imagine has their own way of paying to regularly receive surprise stuff in the mail.
They've evolved way past "a Funko Pop and some pins with superheroes on them," and now there are subscription boxes for Japanese snacks, board games, and Dungeons & Dragons-themed t-shirts. None of them deliver anything you need, but some of them bundle together things you might want.
Are they really worth it? That depends how much joy you get out of surprises and receiving things in the mail, but if you're deep into a fandom you already know whether collecting trifles related to it will make you happy. And subscription boxes make decent gifts—like the old standby of a magazine subscription, they guarantee the receiver will have a reason to remember how generous you were at regular intervals for the next 12 months. And that's priceless.
CultureFly's boxes aren't cheap, but rather than offering a random selection, they're extremely specific. You can subscribe to the Star Wars Galaxy Box or World's Finest (for DC Universe collectibles), but there are also subscriptions for fandoms less catered-to. Like The Office Box, which once included a replica of Dwight's stapler suspended in jell-o. That's something you won't get anywhere else. They also have subscriptions for fans of SpongeBob, Supernatural, Naruto, Friends, that one cat called Pusheen, and etc. CultureFly delivers four times a year, and prices vary—for The Office Box it's either $40 each or $144 for a year, while the Star Wars Galaxy Box is $50 each or $180 for a year. At least shipping is free.
A serious dice habit can be a hard thing to kick. I once saw a man sell his own kidney for a set of machined transparent Gamescience polyhedrons. If you're in danger of falling into the same hole, factor a dice-of-the-month club into your budget to sate the beast inside you that thirsts for speckled d20s. LibrisArcana's premium dice subscriptions start at $15.50 per month, with free shipping worldwide. As well as a set of resin dice every month they add little bonuses like stickers, and sometimes just more dice. They also offer pricier options like the premium metal RPG dice subscription for $22.75, which gets you seven dice so solid you could kill a goose with them.
Delivering a bi-monthly version of an escape room you don't have to leave the house for, Escape the Crate is basically selling LucasArts adventure games. One crate might have you (and optionally up to five friends) solve a murder during a lock-in at a 1920s speakeasy, another will see you repair a spaceship on the moon. The puzzles are presented as props and papers, some in sealed envelopes that ominously read DO NOT OPEN UNTIL INSTRUCTED, and you get a link to a website with audio versions of the instructions and narrative as well as hints if you need them. At $30 plus $10 shipping each they cost a little more than you might pay for a ticket to a real escape room, though just one of these works for a group. They can also be reset to play again or share, thanks to downloadable replacement printouts.
Of the standard "mystery box of pop culture junk" subscriptions, Geek Fuel are one of the more well-regarded. Rather than being padded out with stuff you could get at the Dollar Store, their boxes contain limited edition figures and exclusive t-shirts. If you're really into the latter, they have a Tee Club subscription, and if you'd rather buy a box where you know what's in it they sell those too. For $35, there's a '90s gamer bundle with a PS1 button-masher tee, a "Sleep Fighter" throw pillow, a PlayStation metal coaster set, and console decal. (Sadly it does not include '90s PC gamer gear like a keyring with a tiny replica of your first 486 or a Windows for Workgroups hoodie.) Geek Fuel's monthly plan is $29 plus shipping, and if you pay for a few months in advance you get a discount and a bonus shirt.