For general "throw-away" type notes, I do much the same, using scrap pieces of paper I have around the office before recycling them (great use in my tickler file). For meetings at work, I'll usually have either a notepad or a Blueline A9 notebook with me. However, for being out and around, I'm liking the pocket sized Moleskine with a Pilot G-2 mini for the quick thoughts. When I get back to the office or home, then I can just throw it in my intray, and process it like anything else.
And its sturdy, standing up well to shirt pockets, coat pockets, even the back pocket in a pair of jeans.