From a corporate network I had a need to jump to one system, and through it to another in order to have an open web proxy to another 'internal' network - or in this case it was a lab network where I had to hit a openstack Horizon dashboard.
It's a somewhat simple concept and I was sure SSH could do it but I had some trouble figuring out how.
The scenario looks like this:
my macbook -> ssh server <- INTERNET -> second-ssh-server -> browse internal network
Note that the second ssh server was running sshd on port 22000, you probably don't need that.
The command I came up with to accomplish this was:
ssh -t -t -v -L9999:localhost:9932 root@ssh-server ssh -t -D 9932 root@second-ssh-server -p 22000
A whole blog-post for one command? Yes, it was that cool!