It wasn't exactly a New Year Resolution, but near the beginning of last year I decided to give up soda. I went from having one everyday to perhaps 10-15 sodas over the entire year. Started drinking green tea everyday.
There are a lot of things that I'm trying to do. The problem has been consistency. Results come from consistent effort applied over a long period. I'm trying to exercise everyday, meditate everyday, write everyday. Perhaps my main goal is to finally make a genuine, legitimate effort at obtaining a relationship. I've made a lot of progress in that direction, just need to be more consistent in my efforts.