The Pocket Notebooks of 20 Famous Men
artofmanliness.com
artofmanliness.com
I suppose if you're a scrawler, this can be tough but I imagine a lot of HNers have plain but legible printing that could be OCRed and made searchable, which seems like a big win.
α http://www.amazon.com/Moleskine-Square-Notebook-Pocket/dp/88...
β http://www.amazon.com/Book-Memorandum-Green-Log-pack/dp/B000...
Square ruled notebooks happen to be the only way I can keep my Seinfeld calendars going, too.
As items are completed they are crossed off. Once notes get too crowded or most items have been checked off or crossed out (completed), I unfold the sheet, copy incomplete items to a new folded sheet and put the the old sheet in a file.
I always keep a half-burnt papyrus with me, like Archimedes.