I've been wondering if those still exist i've seen the username "Rai".
And is there anyway to obtain this "3-letter name" thing?

Yeah, pay an admin a bucket load of $$$

Same applies to pretty much anything 'non-standard'.

Actually, there's a bug in one of the older Toribash versions where it will let you register 3 letter names (still works). So much for the corrupt staff system, eh Piggy?

Nah, that used to be the case but a while back we decided to standardise everything instead of letting admins conduct their own deals on stuff like that.
For profile customisation you're pretty much limited to this stuff or whatever you can do to your own account with tp/vip.

The only customisation done directly through admins now that I can name off the top of my head are name changes.

So yea nah, no way to get a 3 letter name.

Edit: Ok TIL there's still a way. Ggwp Gynx.