The Rhodia No. 16 Notepad has to be my favorite pad of all time. Size A5, or 5.8 x 8.3, this pad fits neatly into my purse, backpack, padfolio, or hand. It's a great size to have around for note-taking, swabbing ink colors, writing affirmations over and over and over, working out ritual murders of (for purposes of this blog) unnamed a$$holes and inheriting all their money (beats counting sheep when the insomnia kicks in)--whatever takes your fancy.
I have at least 7 Rhodia No. 16 pads, and two "Kindofs"--a Clairefontaine Pupitre pad that is the exact same size as the No. 16, and a Mnemosyne No. 188 pad that is also listed as A5 but just slightly larger (the two black pads at the upper far right of the pic).
I seem to have mostly graph and lined No. 16 notepads, just one blank and only one dotPad--so far. I'm planning on picking up a few more dotPads, as they seem to me to be the best of them all: the dots give you a way to write straight down the sheet, but aren't as intrusive as graph or lines. But the pad isn't blank, which is nice to look at. I think this comes as close to being the perfect pad as I can get. The four pads in the pic are, from top left going clockwise: lined, dotpad, graph, and blank.
Anyone else have a Rhodia favorite size/number?