I found out about
Nerd Block by accident. My fiancée's roommate ordered a Loot Crate and when it arrived we all oohed and aahed and promptly went looking for more of these monthly mystery boxes online. And there, among many others, it was: Nerd Block. What we all liked is that this particular website lets you choose a theme. There's Nerd Block Classic ("Comic Con in a box"; a mixture of geeky things), Nerd Block Jr. Boys (geared at young boys, but can include things like Pokémon, Skylanders, Nintendo, etc), Nerd Block Jr. Girls (geared at young girls, but can include things like My Little Pony, Polly Pocket, Hello Kitty, etc), Horror Block (as the name says: aimed at the horror franchise), and they've now added a new one: Arcade Block (aimed at video games).
Although it seemed appealing to try them all, I decided to stick to the Horror Block, because I absolutely love horror films, books, stories; you get the picture. I subscribed immediately, with the idea that I'd only get it one month, but I've already changed my mind on that one and will keep my subscription a bit longer. XD The Nerd Blocks cost $19.99 (or $13.99 for the Jr. ones, which don't include a shirt) plus shipping. For me shipping was $12.50, but it's fast, includes tracking and, really, it's worth it. (Plus, in euros it wasn't bad at all.)