Moleskine Ruled Notebook
In the course of my working life I spent several years as a computer tech, and have consequently learned a healthy caution regarding the frailty of electronic devices. The Pocket Moleskine has been the most reliable PDA I've tried. Compact enough to fit in any pants pocket, the covers are stiff enough to provide a firm, stable writing surface even when standing and yet still pliable enough to be comfortable even in a back pocket. A previous reviewer said he expected a notebook "the size of a DVD case". Two points in response: how many DVD-case-sized pockets do you have, and why didn't you order the larger Moleskine? He also complained that he could only get one sentence on a page in his Moleskine. my own handwriting is of a normal size, and a quick check of my most-recently filled Moleskine shows an average of 130 words to the page.
The Moleskine is filled with good, smooth acid-free paper that can take a wide variety of inks without smearing, discoloring, or bleeding through. The expanding pocket is well-secured and can hold a surprising quantity of loose notes, receipts, business cards, etc. The books themselves are well constructed and durable; mine are exposed to hot, humid conditions and hold up to daily carry and use.
The other reviewer pointed out the price: certainly these are not 79-cent Office Max specials, but for the serious writer, or a person who must record important information through the course of a day and retain it legibly for more than a week, the price is worth it. One hint to extend the capacity of your Moleskine: use the bound pages for things you want to permanently record, and keep Post-It notes inside the covers to jot down quick memoranda. I use the Post-Its for such things as the titles of books or movies I want to research. (Think of the Post-Its as expandable memory for your PDA!)