Weight Tracking Software

Specifications:

.indivudual user logins.
.users enter their current weight daily, with an optional note.
.system keeps track of historic weight.
.system generates an average weight using a exponentially smoothed running average (not very complicated, really)
.system can create graphs of weight over time, average weight over time, or both.
.users can enter any number of goal weights.
.system will estimate time to complete the goal.
.Users can query to find their weight on a specified future date, their average weight for a period of time specified (in the past, so like an average of the past month, or the past week, etc)
.users can specify the level of public access to their data; either no access at all, access to look only at graphs, or full read-only access (no updating numbers)