Joining in! I am using this sketchbook:
It has 100 pages, but a couple were ripped out from old sketches I did last year something, nothing worth staying in.
So just like about 95 pages left.
The medium I decided to use are the Faber Castell's Pitt pens - 6 shades of Grey, 4 classic big brush (sepia/burnt orange/gray/black), and 3 blacks: Fine, Medium, Bold. (So I can at least use them, and not leave them lying in my desk drawer!!)
I've decided this sketchbook will be dedicated to all things of October.
It'll keep me creative/busy enough.