What is the importance of learning "entropy?"

Ever since I was a kid, I can appreciate the real world applications of everything I learned at school. I helped my friend make a life-sized version of his drawing while we were at kinkos and I thanked my Algebra lessons, for example.

Whenever I have a new lesson, I can always think of ways I can use that particular knowledge in my day-to-day life -- until entropy.

I've read its wiki, but I am still confused because I kept returning to a sentence my Physics teacher told our class: "When you pour hot coffee into a cup, you change the entropy of the universe."

WHAT? Whoosh! It didn't help that I was a waiter that time, so I kept thinking of that sentence every time I pour coffee!

So there. If I finally get to grasp what entropy is, where can I use it on my daily activities?

Thanks.