CNExtend is a great extension made for Firefox browsers. It can tell you the effects of adding/removing improvements/wonders for one thing (AMAZINGLY helpful in trying to decide what to buy). I recommend it if you use Firefox normally, it's unobtrusive and has other features.
To download it go here: http://www.babelphish.net/cnextend/download/
If you need any help with it let me know.
To download it go here: http://www.babelphish.net/cnextend/download/
If you need any help with it let me know.