As someone with ADHD, there is no end to the number of things that fascinate me in life, and as such, I tend to obssess and nerd out on a lot of things. Probably my biggest nerd things are this:

Sonic the Hedgehog: I was gifted a SEGA Game Gear with Sonic 2 for my 9th birthday (30 years ago) and I loved everything about the world and characters. I've been a loyal fan ever since. I own every American comic book that's been released, I've seen all the various shows and movies, and I've played most of the games (minus the rare arcade games and games on consoles I never owned, e.g. the Nintendo DS). I even built a website to keep a logical reading order of all the main comic series that have been released. It's a few months out of date right now; my personal life got super busy these past few months, but I'm finally free to update it again. It's considered a valuable resource in the Sonic fandom, as the comics can get really confusing without a reading order to guide you. Especially the old "Archie Comics" Sonic series. They had so many miniseries and spinoff comics that it gets confusing really fast.

James Bond: I dunno why, but I really got into spies back in jr high school. Back then, I loved the movie Harriet the Spy and enjoyed the film GoldenEye. The video game GoldenEye 007 came out for the Nintendo 64 and my friends and I were obsessed with it. Then my dad bought me two VHS collections (yes, I'm old) of all the James Bond films and I spent my summer vacation nerding out over all the old films, from the '60s and onward. I learned James Bond was the origin of so many action/spy tropes I had seen parodied in cartoons and movies. The bald villain with a scar and a Persian kitty in his lap. The gadgets, the cars, the well-dressed gentleman spy, plots to rule the world, etc. All pay homage to James Bond films. I really got into it.

I especially loved learning about Ian Fleming, the original author of the James Bond books, and how he was a British Naval Commander during WWII and worked Intelligence for the allies. His work was more boring desk work than save-the-world action, and his original novel version of Bond definitely had more desk work than his movie counterpart. I actually did a whole James Bond movie marathon, including all the official and non-official films, and reviewed them in depth on my movie review blog. I even compared them a little to the books they're based on, where it was applicable. Most of the movies are completely independent of the books. Some only share a book title and nothing else, e.g. Moonraker. The books and movies are very different from each other.

Movies/TV shows: As you may have guessed from my last link, I also nerd out about movies and TV shows. I've watched thousands of films in my life and hundreds of TV shows. I still consider it a fun hobby; I haven't gotten to the point of learning about filmmaking techniques, obsessing over actors or directors, watching awards shows, etc. But I really enjoy getting lost in a good story for an hour or two, and I started a review blog to analyze and break down just what is so good (or bad) about the storytelling in movies and TV shows.

My last movie marathon (a Studio Ghibli marathon) was interrupted by an Internet outage and I haven't had time to pick it back up in a long while. But I finally find myself with loads of free time again, so I might finally complete that marathon in the coming months.

There are so many other things I'd consider myself a nerd of, but these are a sample of the larger nerdom topics I enjoy.