This app was mentioned in 1 comment, with an average of 1.00 upvote
The basics are this:
Check the site whenever you want to have a cigarette.
Cigarette cravings tend to go away in 10-15 minutes.
It breaks the day into 15 minute blocks.
Over the course of 9 days, it blacklists 15 minute blocks. Eventually all 15 minute blocks are blacklisted.
In the beginning you rarely/never need to wait more than 15 minutes. It gradually gets you used to waiting longer and longer.
If anyone is interested, it also has an android app
AMA I guess?