Having a monitor that rotates can be a big help if you read 2 column PDFs at a desktop. I hate having to scroll up and down the page to read columns. Most monitors do a great job when rotated 90 degrees.
I also use blue light filters pretty much constantly to help reduce eyestrain. I tend to buy the core books in hard, the ones I'll use all the time, but more peripheral or just for interest books as PDFs. Part of that is the immense cost of shipping anything to where I live, but I also only have so much physical room for gaming books.