I used to use sslh. So its this tcp server that looks at the 1st bytes that are sent and identifies if its ssl(https), ssh or openvpn and "port forwards" it to the correct server. So you can run all on 443. Quite an interesting concept, specialy to bypass "proxy only" companies.
that way you can place a nice hello world, or a corporate mail box face on the https part and the proxy administrator will allow it.
then use what ever you want via proxy connect.
One of my favorite activities was to open websites i know that were blocked in front of the proxy administrator.
I would not make a fuzz about it, just casualy open and close like i was actualy interested on the webpage.
and then see the guy running to his desk to check the block list 🙂
"how did you open that?" and i was like: "maybe there was some temporary error on the proxy?? it just allowed me!. let me check now? now its blocked, weird!" the good old days
"dude, have you checkd the black list? here is my ip! you need to find the issue fast! imagine our boss finds about it?"