I know many offer web site space for their subscribers on their servers, but generally their TOS (terms of service) state that they don't allow for personal web severs and if you want that you need to upgrade your service (more $) Some ISP's will block the common tcp port 80 for web servers. There are ways around this of course, but if you are caught, you could loose your connection. You could consider this as an alternative to running a local server, of course you would have to have their banners.
Check out this site, where we played a practical joke on a co-worker and kid-napped one of his Star Trek action characters that he has in his cube, had it free hosted, and then sent him anonymous emails to go to the site. It was a real hoot.
Read the original message (link) and view the other links back from right to left (2nd msg, 3rd msg etc)
Then do what SK8 said ^ and forward the tcpip port (80, 8080, 56 etc, whatever tcp port your local webserver is listening on) to the tcpip address of your local webserver (192.168.xxx.xxx) If your local server is listening on something other than the default of port 80,(say 8080) then on your browser address bar you will need to specify myservers-external-ip address:8080