Sometimes you need to indulge, but don't have any money to spend try any (or all!) of these ideas.
1) Take a bath. If you don't have a bathtub, take an extra long shower instead.
2) Eat more slowly. Savor each bite.
3) Reread your favorite book.
4) Go for a walk and make an effort to notice the beauty around you.
5) Take a nap.