revchad wrote:
http://spaz.ca/cronometer/
Open source, free, and works great for me. I find it easy to use, and it tracks diet macros and micros and you can set the targets it uses bar graphs as well as percentages to tell you how close you are which makes it easy to process the information. You can enter weight, resting heart rate, and blood pressure and get charts for over time.
I especially find the reports function useful, as you can set a time span (e.g. this past week) and it will give you your macro and micro averages, which is nice if you overeat a little sometimes and under eat a little sometimes and you want to know how it adds up to adjust your diet accordingly.