
Everyone on the securityfocus mailing lists (for computer security issues) is named either "Susan Bradley, CPA aka Ebitz - SBS Rocks [MVP]" or "KillerCrab".
Calling yourself something like wirePan1k or theDarkYam is 1998. And putting your professional initials after your name says déclassé, loud and clear.
It reminds me of people with nonmedical doctorates who insist on being called Doctor, put it on their stationery, etc. My brother was warned about this when he got his: "Don't call yourself doctor at a hotel if you don't want to be awakened at 4 am to help a heart attack victim", etc. It's especially true of people in disciplines that feel inferior. Podiatrists list themselves as "Dr. Richard Smoker, DP". Same phenomenon with optometrists, chiropractors. You don't see people with doctorates from good schools in comparative literature or chemistry doing this; they're not in need of doctoral authority.
The worst of this phenomenon is the mediocre academic, often a big wheel at a small crappy college, who insists on "Doctor" followed by his first name, which is often a diminutive. "Dr. Billy" or "Dr. Heidi" wants to be everyone's jolly pal and also maintain white coat authority.
Our nation's examples of all these phenomena are Dr. Laura and Dr. Phil. I should stop criticizing LadyLaser and PhreeDisk; far less harmful.