Before I go to sleep, I run through what I did the whole day and be thankful for everything. That I'm alive, that I had a hot shower, that I have a heater, I have to eat.
This also help me remember what I did the whole day and evaluate everything in a positive manner. The whole thing take me like 5min and it changed my life since I started doing it. It doesn't matter whether you believe in god or not, being thankful will make a difference in your life. Try it :)
I am thankful to the people who make the free software that I enjoy using. Off the top of my head: NetBSD, Firefox, Mame, Vim, FLAC, Lame, MPD, Scrot/FEH, Ratpoison, and Scrypt.
Nice friends from my hometown! I've been working abroad the past eight months, and they've been loving enough to keep in touch with me every once in a while.