I'll go first: Sitting on a shelf near my computer, I have Dictionary of American Slang, Webster's Collegiate Dictionary (11th Ed.), Goode's World Atlas (1970 Edition), and a heavily worn copy of Strunk and White's Elements of Style, which I bought for English 101 back in 1967.
What references do you keep handy while writing?
"Any book not worth reading twice was not worth reading the first time." Oscar Wilde
The Concise Oxford Dictionary, the Handbook of English, which is a battered old paperback I've used since I was in high school, a French dictionary, an Italian dictionary, and the Bescherelle for both French and Italian verbs. Also the Brittanica Book of English Usage and Roget's Thesaurus.
I also have several on-line dictionaries in my bookmark bar for quick and easy consultation.
1) when writing where there isn't any Internet, my iPhone so to look things up.
2) I keep each story in its own file on my laptop. Each file has sub folders with character references like their histories, important events, ect. The resource folder also contains the world bio, technology, weapon systems, strengths and weaknesses to each piece of tech, and where my science to be applied to the book came from.
3) I have a drawing not pad at home, in it are drawings of things such as rooms, clothing and vehicles. When things won't add up, it is a good idea to draw it out. Using a 3d program like lightwave helps create the world to scale. (Example)
She turned off the water and faced mark. "Well, do you see anything you like?" She said and waved her hands across her body. She smiled at Marks discomfort. "If you are going to stand there and watch, can you hand me the towel?"
"Right, sorry Jenn." Mark said and fumbled with the towel rack. He took two steps toward her and handed her the towel.
Jenn took the towel from Marks hand, her eyes glanced to his groin. "If we're going out tonight, you'll need a shower." She said and smiled as she wrapped the towel around the back if Marks neck and pulled him in close for a kiss. She grabbed his shirt and lead him into the shower stall where she reached for the water controls.
As you can see, the bathroom is a tight space, and if you have a economy sized room, how many steps can by our characters take in such a bathroom?
My bathroom wouldn't allow more than two steps from the door to the wall. One step for the shower. So drawing the world can be important to the environment and or the characters development as it tells you a lot about the wealth of the character by way of the size of home they live in.
I agree with that assessment of the requirement for drawings. I am in the middle of a long novel on the adult site, in which I have three people sharing a house on The Magothy River in Anne Arundel County, Maryland. In order to make both the indoor and outdoor activity realistic, i had to draw floor plans to scale for the two story house; a large scale (1"-50') plan of the lot on which it is sited, complete with North arrow and landscaping; and a vicinity map of the surrounding roads. I also have an Official Maryland State Highway Administration road map folded inside the back cover of the spiral notebook in which I have the drawings. But the only one of those things I would consider a "reference" is the state highway map; all the rest are figments of my over-active imagination. And, since I don't keep it handy, except when I am working on that particular piece, I didn't mention it.
"Any book not worth reading twice was not worth reading the first time." Oscar Wilde
My MacBook Pro has the dictionary app with contains The Oxford American Dictionary, The Oxford American Writer's Thesaurus, Wikipedia and Apple Dictionary. I also only write on the computer so I have the entire internet available when WiFi is there. I am a Geographer, so I have scads of Atlases and maps available for use. I also use my Universal Translator app for translating unknown phrases or words, or converting English into dozens of languages. I also have hard copies of The Second Edition Cambridge Encyclopedia, the Oxford Spanish Dictionary, a Seven Language Dictionary, Goodes World Atlas 18th Ed., the illustrated Great World Atlas, and the ever reliable Webster's New World Dictionary-Second College Edition. Not to mention several different versions of the Bible and other sacred writings. Strunk and White are always there.
I guess it all depends on wht type of story I'm writing. Obviously I keep a couple dictionaries around (two in case I lost one) a thesaurus, and a vocabulary builder. I probably should by a book on grammar... everything else I use google and other search engines to fine info on different things.