The large Moleskine Sketchbook is my favorite day in and day out sketchbook. The thickness of the paper is very appealing and I like the slight yellow tinge to it as well. It's great for both inks and pencil, and holds up well to how hard I bear down when I draw.
It's also nicely portable and not too small, measuring 5ish inches by 8ish inches. There is a small pocket-sized version available too, but drawing in it isn't nearly as nice an experience.
Here you will find a list of all posts tagged with Moleskine Sketchbook.