Research on positive neuroplasticity teaches us that taking time to intentionally notice the good things in life can help us to feel better over time (see http://www.rickhanson.net/the-science-of-positive-brain-change/). It's a simple practice that can shift how we see the world, as we seek out the good that we might otherwise overlook while we are distracted with the day to day stresses of life. As our minds calm during this practice, we are also more able to access our internal strengths (like creativity, problem solving, perspective) to cope with difficult situations. See http://www.rickhanson.net/wp-content/uploads/2009/09/Taking-in-the-Good.pdf for tips on how to practice.
A friend introduced me to the idea of keeping a "happy book" about 20 years ago and I still enjoy noting random things that make me smile. Here are a few samples from over the years:
-fixing something myself
-little kids who always put their clothes on backwards
-the sound of rain on a tent
-being missed
-ferris wheels
-the mysteries of old suitcases
-a well stacked wood pile
-really wide scarves
-peppermint essential oil
-fog
-rearranging furniture
-reinventing leftovers into something new and delicious
-finding strange t-shirts in thrift stores
-red shoes
-people with soft eyes
-the warm spots cats leave behind when they move
-dependable pens
-dependable people