Tunnel Through HTTP Firewall

I was asked by Christopher if I knew of any way to do VPN through a firewall. Or to do SSH through a firewall.
My initial response was that I'd read that there was a technical problem of making SSH or VPN packet fit the HTTP protocol. In other words, a number of firewall programs expect to only see HTML and HTTP headers, and will strip out anything else.

Reading between the lines, I believe there are some solutions that take advantage of HTTPS and HTTP/1.1. HTTPS is a secure connection method for web pages, you see the closed padlock on a number of browsers with this. It is used to seeing a bunch of encrypted data. HTTP/1.1 allows a continued connection, with the potential for bidirectional data.

I did some searches on "SSH over HTTP" and "VPN over HTTP" on Google, and then added a search for "HTTPS CONNECT ssh" (CONNECT is the method that HTTPS uses). I found a few entries. The main one is:
CorkScrew
Others:
HTTP Tunnel
Proxy Tunnel at Sourceforge
SSH HTTPS Tunnel Perl Script

I have no idea how or if any of these solutions work. I'd love to hear if anyone tries them and find out how they work!