In the official blog a few days ago, it was announced there was a new set of last names to go along with the SecondLife Birthday. A number of them go along with the theme of the event, elements.
In addition to all of the exciting events, we're thrilled to unveil a
special series of SL21B themed last names. Embrace the elements with our
new Earth, Wind, Fire, and Air themed options!
The names are: Cirrus, Blowhard, Windyfloofs, Cinder, Hotman, Pyroclaw, Boulder, Soil, Pebblepaws, Ocean, Torrent, and Frostfangs
The notice didn't say how long the names will be available, though probably at least until the end of the Second Life Birthday, on Sunday July 21.