Basically, you could set up a webserver to listen on port 8000. Then, in somones browser, they would type http://www.whatever.com:8000 to connect to you. Or if you moved telnet to 6969, then they would have to know to telnet to that port. So if you ISP turns off incomming port 80, you can move it, but the other end has to know also. That basically describes both sides. You can't say, I want AO to show up at port 7251, because AO has to do it.

Tunnelling outboud telnet via http works if you telnet to port 80 on the remote machine, and they have moved telnet to port 80. That is it. This tool is not used maliciously in any way, and it only works for your machine.