Since SSL doesn’t support more than one virtual host per IP/port pair and I want to run a few vhosts on my server, I am using port-based SSL-vhosting. This worked well for a while and I was using 443, 444, 445, 446 and so on.
Then, MS comes about and decides they need to use a new port number since they’ve tweaked CIFS a little. What number do they choose? 445! And what happens the first time some random hole in their implementation is found? The university stops incoming connections to port 445. Not rejects or anything nice like that, no. They just drop the packets on the floor.
I just love it when people make random changes like that without telling. And I am so happy about MS grabbing random port numbers.