NetworkStuff .net maybe as early as 2006-04-10.
Related Post
Digital HoboDigital Hobo
.org, since Nov. 30, 2008. .info, since Nov. 30, 2008. Where was also a .biz, between 2008-11-30 and 2017-01-10.
Rick7425Rick7425
Rick7425, .com and .biz, the last of many, since at last 2007-01-17. .us, and .net existed until 2017-12-17 (or so). Along with a .info, .ws and .org until (approx.) 2016-12-18.