Player games database

It would be really useful if members could store games by opening / variation and there was some sort of analysis feature.

What I have in mind is that when I review my games I can pick out all those which I have played, say, Kings Gambit and review the individual lines and results of those lines and then add my analysis.

Some sort of tree showing the moves and number of games played with those moves would be an added benefit.

To pick up other players games in the same way would also be a tremendous benefit and would save me time trawlling through their games looking for how they respond to the lines I intend to play.