Quick and easy ways to feel better:

1) Be grateful for every specific thing you can think of; e.g. "I'm grateful for the trees," "I'm grateful for my eyes," etc... Just try it for a minute and see if you don't feel a LOT better.

2) Do something nice for someone.

3) Exercise. Walk, run, swim, ride a bicycle, do yoga, or tai chi--whatever.

4) Sing a song.

5) Eat sushi with a friend.

6) Watch a Steve Martin movie.

7) Dance.

8) Go to bed early, get up early, stretch, take a walk, cook yourself a nice breakfast, and then do some of the things on your to-do list. You'll feel like a hero afterwards.