Use the alarm clock on your phone. You can snooze it for 10 minutes at a time. Each alarm can be given a description. And if you have a task to do weekly like say sign your time card you can set an alarm for a specific day of the week. The upside, its already on your phone. The downside, you have to do your "todo" list one week at a time. Just about as simple as it gets.
I use Springpad for my to-do list, but that might be more complicated than you're looking for. I use to store my recipies, my to do list, and shopping list, and I can edit things from the computer, which can be more comfortable than trying to do everything on the phone.