4x6 inch index card weekly calendar + notes
In Acrobat Reader, I did a "scale to fit printable area" on 4x6 inch index cards. One side is grid and one side is blank which turned out to be quite handy for this experiment. Shown with a regular size Pilot G2 pen for scale.
Lefties can simply smurf the other side of the page. Those using anything besides the Circa/Rollabind system can still do this and hole punch the index cards for a handy & portable DIY calendar.
Why 4x6 cards? 3x5 seems too small for me to have a reasonable amount of space to write and also I'm fairly sure my printer doesn't handle printing on 3x5 cards. People with a printer than can do 3x5 cards should be able to scale down to that size and still get a good result.
Using a top-bound hipster PDA (such as the Circa PDA?) Just rotate the card 180 degrees and the print so the big blank space would be on top. I think that would work :-)