Learning how to use ansible to configure my laptop has reduced my stress levels a lot: now if I don't remember something I can just check the ansible playbook, and mostly importantly whatever happens I know that in a few hours I can go from nothing to a fully configured laptop with everything that I need on it with almost no manual intervention:

* install debian from netinstall with almost no tasksel (ok, this requires some accepting of default values and a couple of personal choices)
* put a public key in /root/.ssh/authorized_keys
* run ansible to install everything I need and do all systemwide configuration
* login as my user and run mr checkout to clone all repositories with my projects, data (git-annex) and dotfiles (vcsh) to configure whatever is left to be configured per-user

Up to now I've only done it to configure a new machine / change hard disk, and that was completely stress-free; I guess that in cases that are not planned there would be a bit more stress, but much less than the alternatives.

Of course, this approach only works with a linux machine and in my setup requires being used to use ssh with a key (this is usually a big source of stress when my SO needs to access my data/project repositories :( )