As I am looking towards becoming a teacher I am also worrying a bit about how I will organize my stuff. I am not necessarily the person with the tidiest desk or the tidiest folder structure. Usually the stuff is where it should be, but it could still be a bit better organized. To help me with all the worksheets and handouts and such I will produce and need in the years to come, mostly the next two, I am looking at using a document management software to help me get my stuff sorted.
I am not looking into some really heavy enterprise stuff. I want to be able to have a program that I can tell which files I have with categories such as tests, content as well as subject with an exhaustive search function. It needs to be able to handle various different file types, at the very least the usual office stuff and sound files. Basically it needs to allow me to add metadata to just about anything and search for that. I use my home pc and a netbook, however not a server however I would love to have access to the db and possibly the files on both machines. I am a heavy dropbox user, so that might be an option. 
It is late here and quite hot, so I might be missing a whole lot of things I might want or need or must to have.
I am open to a bunch of ideas outside of "suck it up and sort your shit manually".
 Privacy reasons concerning student names and grades would make this less ideal if I want to handle that stuff digitally. This is only up for bonus points, though.
Ninjaedit: I looked at wiki but there were so many options with none sticking out as the obvious one. Also free > pay though it depends on usefulness. I am not yet raking in massive amounts of money, just a bit more than a regular student.