Deeply inspired by Paulo Cereda's answer on the ways TeX can be used apart from document creation. If you haven't seen the program mentioned: it's a Reversi TeX game that during the compile asks the user for the next move in the game and provides feedback. At the end the whole game is produced as a dvi.
Immediately practical uses of this popped up: Asking users for layout, colors, language. So on to terra incognita!
I tried to dissect the Reversi game, but it's not written for readability. I searched around, but user input to TeX programs is not an everyday thing.
How do I take input from the user compiling the document?
For example, I could ask a user for their name, and then print "Hello, [user's name]".
Update 1: I've now stumbled upon the
\read macro, and it seems to be on the way, but it isn't really what I want.
Update 2: David Carlisle pointed me to
makebst a program to generate bibTeX styles. I'm looking into the source.