Same here, I buy a pretty diary because, well, I love stationary - but then give up using it half-way through first term. I use google calendar, or at least I used to. The lab I worked in used it to book specific rooms, so moving my e-calendar to google made life a whole lot easier. I just have to accept that all those beautiful paper diaries are not for me.
I do, however, use note pads when I meet supervisors, go to seminars etc. Amazon kindly informed me that there is something called conference organizer (e.g. http://www.amazon.co.uk/585101-Conference-Organiser-Elegance-Mechanism/dp/B001F5Q87I) and now I consider getting something like that as a compromise. Especially since my paper diaries were usually full with random stuff I collected over time and the organizers seem as if they could hold quite a bit. Anyone used one before?