Few days ago, I read a funny document "GTD for hackers" and found an interesting ideas there. One of them is to create the checklists for routines.
I already use Things by Cultured Code, to track my todos. However there is no such feature as periodical tasks. They should behave like periodical events in the calendar — you add it once, specifying a time interval, and task should appear in the list automatically. Things is lack this feature.
But we have this wonderful Apple Script, and it allow to do almost anything!
I spent about hour to generate a 10 lines script. It adds a task to the Things right from the command line. The last part was pretty easy — to run a crontab and to add a one line for each periodical task I want to appear in my checklist.
Finally, I've got a very flexible system, which solves my problem and does not require any additional software.
Sources are available at the GitHub. Fork and edit.