Here's my problem:

I want to set up my computer to be a web server, so I don't have to abide by some free provider's rules. I got a program that allows me to do this and began building my site. The only problem is that nobody can access my site from outside my network. I can access the site from within the network using my internet IP, so I know my router is forwarding port 80 to my address. I checked all the other settings on my router, and they look OK. This leads me to believe that my cable modem provider is blocking that port. Is there any way I can get around this, like set it up to listen to a different port or something? Sorry if I sound stupid. I learned everything I know from experience, so there are holes in what I know.