Recently, I met a couple who were very dedicated to following the program outlined in the book Your Money or Your Life. I have not read the book myself, but it is my understanding that (among many other things) the book challenges you to think about what your time is worth. While I like the theory, I find it very difficult to put a price tag on my minutes, especially considering the fact that I am absolutely worthless right after lunch.
My take- away from the meeting is very watered-down, but still helpful. I now think about how many hours of work it takes to buy something. For example, if you earn $30 an hour, it would take two hours of work to buy a pair of $60 shoes. In addition to a level of awareness it brings to your spending, thinking about two hour conference calls can spoil the fun of shopping.
If you would like to take this concept to the next level, try this time value calculator from MSN. I also enjoyed reading this great post by Trent from The Simple Dollar.