I use very long passwords for everything, even with the lamest accounts I have. I require my kids to use at least 14 character passwords on our home network and I’m considering issuing them smart cards. No one else, not even my wife, knows my network password.
I don’t just throw out shredded documents; I spread the shredded bits into my garden to use as mulch.
I don’t do it because I think someone is going to go through my trash to reassemble bits of my research notes. I do it because it’s good security. I try to run my own network the same way I tell my clients to.