Bypassing the firewall at work

I couldn’t get back to my home router, not my linux box, not my web page control panel ever since I have changed my job. Because of the very strict firewall policys, I can only use standard ports i.e. http port 80, https port 443 and ftp port 21. Other than those 3 opened ports, I couldn’t do anything else! I couldn’t telnet to my router (port 23), couldn’t ssh to my linux box (port 22) and couldn’t get to my web portal (port 8080).
I don’t understand why they block the ssh port. SSH is a secure protocol and i don’t see how it can harm the company’s network. Anyways, I am trying to find a way out of this when I am at work, at lease I can get back to my Home CCIE Lab for some Lab work. Since Port 443 is working, what I did is to create a Port forward on my home router. I forwarded port 443 to port 22 on one of my Linux boxes. Today I got back to the office and immedately start up putty to see if i can ssh to my linux box via the port 443. And yes, it worked! The next thing I tried was to build a SSH tunnel to use with other protocol using putty. Well, all working fine as what I expected. And I can do a lot of thing now including using a remote CCIE lab at home!