A random midnight thought: does anyone use lego as dnd terrain? Yep, of course, some do:
https://youtu.be/wBAkk_DmU7M

Time (in theory) to get close to speed of light with 1 g:
https://setiathome.berkeley.edu/forum_thread.php?id=34381

> Observed from the spaceship, accelerating at 1g would reach 0.77c after 1 year.
Observed from Earth, it would take 1.19 years, and would have travelled 0.56 light years.

In case you need to role play an engineer:
https://en.m.wikipedia.org/wiki/Turboencabulator

A few good examples:
+ https://youtu.be/MXW0bx_Ooq4
+ https://youtu.be/aW2LvQUcwqc

What happened in 80's:
http://www.thepeoplehistory.com/1980s.html
Handy if you're about to run a game in this time.

A book about how aliens and alien worlds could look like:
http://www.xenology.info/Xeno.htm

Funny lotr art:
http://www.corblok.com/

Constructor of random generators and a huge collection of existing ones:
https://perchance.org/welcome
There is no sorting or convenient search, so it's hard to find good ones. But there are good ones. Their subreddit has some links:
https://www.reddit.com/r/perchance

A nice constructor of the character appearance, with pixel art items:
https://reroll.co/
Also, character sheet manager for DnD 5e. The free version art is very limited, though, and premium is a little expensive. However, it still can be a good inventory manager.

An interesting free PnP board game:
https://pearlyn.itch.io/shelter
Speaking of PnP, I print a lot of games. I think the best PnP you can legally download is Love Letter. Just a few cards and a very interesting and simple game. Well, the official download requires registration but you can find it somewhere else. Or download a redesign from BGG.

Ro is a constructed language to make it easy to construct and understand new words.
https://en.m.wikipedia.org/wiki/Ro_language

Just have a look at the dictionary:
https://sorabji.com/r/ro/

A video about making different interesting voices for your DnD characters:
http://www.vocabilities.com/100-voices.html
Basically, it covers what parameters each voice may have and how to mix it.

Kevin Crawford, the author of Stars Without Number, published very good rules for cybernetic implants:
https://drive.google.com/file/d/1ksvJGmYGvJGIFD9cUaW5AO05tIhrVAMy/view?usp=sharing

Cybernetics were one of a few things I felt should be better, and now they are perfect. The only things left that I house rule on top of SWN are:
1. Space battles in mechanics of FTL to be more strategic.
2. Hacking in mechanics of Cyberpunk Red to be more like a funhouse dungeon.

The Traveller RPG has an (in)famous system for generating (rolling for) random backstory events that formed your character. Players either love or hate it. Love because it's a great framework for building an interesting and alive character with a detailed enough backstory. And hate because that's the (only?) system that can leave you character without a limb or even dead before the game even started.

I just learned that Kevin Crawford published a similar "lifepath characters" framework for SWN:
https://www.drivethrurpg.com/product/154238/The-Sandbox-2

They require registration to download the file. Here, I got you covered.

Online character sheet for SWN:
https://www.swnfreebooter.net/

BoardGameGeek isn't quite good for managing and sharing your collection of games. I found something with a bit better UI and filters:
https://kallax.io/

Here is my collection, for example:
https://kallax.io/profile/BZ10S

Still not perfect, though. Would be great to add notes, like in BGG.

Some links related to the Sherlock Holmes board game. Quite useful for playing online.

+ Audio version of intros for each case: https://www.spacecowboys.fr/the-thames-murders
+ Directory, map, and Case 3: https://drive.google.com/drive/folders/1LfejFl6kqaEPZ3VIyZLczjRtowYcB8Xu
+ PDF for old cases: https://wren08.wordpress.com/other-projects/sherlock-holmes-consulting-detective-game/