I had to spend a good deal of time in a hospital recently, and I discovered that
while they provide wireless internet access, it's heavily filtered.  They also
block things like SSH and IRC which I found to be quite annoying.  After my
first stay I devised a work around so that I could get some things done from
that place.

First, since they allowed port 443 for SSL connections, I started a second
instance of SSH on my home system which listened on port 443.  I copied the
existing configuration, changed the port, and started a second instance of sshd
with the new config:

cp /etc/ssh/sshd_config /etc/ssh/sshd_config_443

The only line I needed to change was: 
Port 443

Then I started the second instance: 
/usr/bin/sshd -f /etc/ssh/sshd_config_443


Once that was up and running at home, the next time I was stuck in the hospital
I used SSH as a SOCKS proxy:

ssh -N -D 5100 -p 443 12.34.56.78

Here, -N specifies not to execute a remote command (shell), -D sets up dynamic
port forwarding on local port 5100 (SOCKS4 or SOCKS5 protocol) and -p indicates
to connect to the remote host (my house) on port 443, which is allowed through
already.  The proxy works great for Firefox for browsing, as well as for Pidgin
(Gaim) for chatting.  Obviously this can be a little slow since the upload speed
from my house is limited, but in general it's a life saver.