I have trac set up for my private and job projects and I have an ability to define tasks or describe bugs there. As most of the time I work at those projects alone, I usually choose to write the TODO lists on sheets of paper. When a task is done, I just strike it out from the sheet. When the full page of tasks is finished, the sheet is thrown away.
I know that I could link svn commits and track tickets by mentioning the ticket number in the commit log, but for me it seems more practical just to write full explanations in the commit messages. What do I miss by not keeping the track of tasks and bugs?
Just for statistics, in the last 4 years of extensive usage of svn, I had to revert back my own projects about 4 times and to look at the history of third-party projects about 20 times, but there was no single case when I had to check already closed tasks and bugs in my own development.