Today, I picked up a pair of khakis. It was on a huge discount. If it was me about 3 months ago, I would have bought it in a instance. Instead, I asked myself "how does buying this add to my freedom?" (refer to The Minimalists and Zen Habits for more on the topic).
I placed it back.
What just happened was that I watched my urge. Instead of acting on it, I observed it.
After that, I pondered and thought about how I would feel if I had bought it.
Buying it would have led to a sense of (temporary) euphoria.