I've got an iPad, Nexus 7 and Galaxy S3 device at my desk. But those guys are just for testing apps. For real work, my tablet of choice is the Staples® Quad Ruled Composition Notebook. Yes, that's a $1.99 notebook. But it works oh so well! The graphed ruling means that I can easily write and sketch on it, and the composition style binding means they don't fall apart.
Here's what they look like:
For years now, I've started off each work day the same way. I draw a vertical line down the right hand side page. I use the far right column to note my TODO list (usually with times of the day when I plan to have the item completed), the middle (narrow column) is where I jot down blog posting ideas, so they'll be ready if/when I get time during the day to blog. Finally, I use the whole left hand page so scribble down notes, ideas, phone numbers, etc. Here's how the page generally looks:
My Dad independently found out how awesome these notepads are, and in the past has required their use as a lab notebook for his students. I think he even uses the same left page as notes, right page as data, technique, too.
For any page or information that I want to store or share electronically, I just snap a photo with my cell phone camera. Problem solved.
The system Just Works. So much so, that I can't imagine replacing it with any fancier device - be it paper or electronic.