Org Mode stored on Dropbox.

At any given moment I have two "running" files - one being a general tasklist, and one being this month's notes.

On the general tasklist I maintain my own, much more detailed, copy of what's in the issue tracker we use. I rotate that file every few months, copying over unfinished tasks. I also use it to record any bug and weird thing I spot with the application, if I don't have time to investigate it, so that I won't forget it and can come back to it later.

The monthly notes file has entries for each work day. Each entry follows the same template:

  * <2017-07-26 wed>

  ** Things I want to accomplish
  *** TODO A task
      Some notes under it.

  ** Other work notes
     This is my scratch area. Here I just type when I need to talk to myself.

  ** End-of-day mind dump
     Here I dump the state of my head at the end of the workday, so that
     I can pull it in quickly the next day.

  ** Jira for today                                                      :jira:
     Here I note down task numbers I want to log time on - at least if
     they don't match the commit log 1:1.

  ** Insight from today                                               :insight:
     Here I try to note down something important or insightful I discovered
     that day.

  ** Things that should be automated                                 :automate:
     A most recent addition to the template - if something is repetitive
     and annoys me, it goes here.

The template is evolving, and I'm not always consistent in actually using it, but I'm trying - and it proves very helpful when I'm dealing with a difficult problem, or for some non-work reasons have problems concentrating. It's also my place for writing down stuff I wouldn't bother (or wouldn't dare) post on the issue tracker.