Ever wonder who wore #11 for the Astros before Matt Dominguez got his hands on it? Think Bob Watson, Dennis Menke, Frank DiPino, Davey Lopes, Ken Caminiti and Brad Ausmus, among others.
Did you remember that Craig Biggio once wore #4? Who did he give up #4 to when he started wearing #7?
Who once wore #00 and who once wore #99 for the Astros?
Baseball-Reference just got better with the addition of the history of every uniform by every number in every organization. Here is the Astros page, but you can see every team page, every player who ever wore #7, sortable by WAR and number of years worn, and all of the retired numbers for every team on one page.
Any blogger who tells you that they can get along just fine without Baseball-Reference is a liar. It is a fantastic reference tool that just keeps getting better.