54 is the Custom Status part of the star/status hack
Also, I will be using numbers 56 and 57 for "DT's Extra", which is a hack that is hard to explain but easy to understand. I'll try to explain it ^_^.
Here at UBBDev, people add "| Something: Something else" in their location field, so it has an extra set of description type things below the user's posts. For example, I have
"Devising new UBB Hacks: Yes!!!" on mine. DT's Extra gives you two boxes in the profile, entitled 'custom display category' and 'custom display item'. By filling out those two boxes, it will automagically put the two things down there, and it blends in properly with the other stuff (Doing it manually here results in everything being bold, instead of just the item; DT's Extra fixes it
It's at about 90% functionality, and will be released the day of UBB 6.1.0 Gold. (or whatever the official name is for it ^_^).
But I digress. We really ought to keep a database of what hacks use what profile fields.