I set up a spreadsheet to calculate my savings and cigs not smoked etc for each day (this was before I knew of 'quit counters') in the hope that it would inspire me and help me through the tough days.
I also wrote a brief note of how I felt on each day of my quit and this has help me more than I could have anticipated. For me, yesterday was the hardest by far (Day 10 btw). What helped me through it was looking at how I felt on other days. There were some when I felt bad, ok and great. What it made me realize is that some days are better than others and that even though I feel utterly sh*t just now, I could feel great tomorrow.
As it happens I would say i'm ok at the moment. But thats a millions times better than 'utterly sh*t'.
So glad I didn't cave last night.