I was in Second Life fourteen years before I decided to go by a display name instead of my legacy name.
Why? I changed personally, the direction of my Second Life changed, and the new name represented the launch of a new era.
When I started SL in 2007 I used my real first name, but if I had it to do over I wouldn’t. It stuck for years though, so when I did use a display name, it made an impact. Some people change display names often, so it’s no big deal. For me, it was significant.
How to change your display name: When in Second Life bring your profile up, and click the name button beside your name. Type what you want in (twice to confirm) then save it.
Caution: Display names can only be changed once a week, so we should probably keep that in mind before choosing something crazy.