I got a power meter (PowerTap G3) last season and looked for a nice program to help me track my activities. With the help of Google and various cycling forums, I stumbled on a great open-source software that fit the bill. Golden Cheetah worked really well to organize my data (by date) and track how my activity went (nice charts and graphs). Combined with Garmin Connect, I could see how I did and see what I need to do next.