I have yet to make a game, though I’m helping with one and story boarding one of my own. My primary medium is the written word, and at times, I can do a surprising amount of research, often just to ensure the accuracy of a two or three line paragraph. Some of the things I’ve looked up include:
A guide to bra sizes and fittings with regards to a person’s height, weight, and build
Realistic levels regarding things like possible weight gain in a month, an actual amount of food a person could consume in a single sitting, and calorie counts. God, lots of calorie counts. I’ve seriously abused way too many diet sites in planning things.
Babysitting and inheritance laws in Arizona (no, I’m not joking)
And, what I consider the strangest one on this list, a Michael Buble playlist covering the bulk of his work. The Rat Pack also makes a large appearance in that particular thread.
I also re-read my old stuff a lot, and tend to keep jot notes in a doc, just to make sure I have as few continuity errors as possible. This isn’t to say that there’s not a lot of stuff I just wing, but I’ve been trying to do that far less then I used to.