I have a server here at cbtr.net that has multiple sql named instances and only 1 IP address. All sql instances are listening on that IP address and they are all currently on dynamic ports. I have created a static DNS entry that looks like this:
CDev A 10.1.1.222
10.1.1.222 is assigned to a server name HorseShoe. The idea is to have the devs connect to CDev instead of connecting to HorseShoe\Instance1.