There are a few pages describing on how to do this, but I thought I would document the process I used (As well as setting up a CA SSL key, and not using the default self signed key) which will hopefully help some people getting it up and running on their Pi.
A web based SSH server allows you to SSH to your Pi via a web browser and does not require and plugins or putty to be installed.
This is handy if you are behind a corporate firewall. Changes are good port 22 is blocked, but pretty much all proxies will allow you to connect out on port 443.
I used GateOne which is pretty straightforward to setup, and then StartSSL which issue free 1 year SSL certs.
Check my out blog for more info on setting it up.
http://blog.gjmccarthy.co.uk/?p=358