The days are big enough that I can write in information, but the calendar isn't too massive that it takes up my entire desk.
And although I use a calendar online, I still like having a paper calendar to record information. And the Business Planner is perfect for keeping up with appointments and expenses. On the bottom right corner is an "expense record" that I can use to keep tabs on expenses.
It's large enough to write plenty of information, not quite small enough to carry in my purse, but it fits nicely in a messenger bag.
I would be totally lost without my calendar. How do you stay organized?
Full Disclosure: I received products free of charge for the purpose of providing a review. My opinions are completely my own based on my experience.