ASP/JSP/PHP... which is best to learn for a Flash Designer?

I suggest that you can learn JSP 1st then, ASP, PHP...because what I know from Flash designer is they already good in ActionScript and ActionScript is similar with JScript. So, you'll get to learn JScript faster and then you can start learning ASP. And hnestly tell you, ASP is easier than PHP (for a beginner in server side programming). You can also try the following url to know more about server-side programming