Moleskines
I used to keep these, and still do to some extent, but a digital Moleskine is actually superior to the paper version. (I have titled my most frequently updated note in Evernote "Moleskine".) Once the metaphor has been "digitized", it's not difficult to fully adopt it. What is different and more superior to digital notebooks are the smooth gestures and agile nature of the hand done with a pen, preferably a gel pen where the ink soaks nicely into the paper. (Leonard Bernstein liked his Blackwing pencils for the look it had.) What is lost in digital is the wear on a real Moleskine, and the fact that you collect them and are visible on a shelf.