I'm glad you asked...
BLURFL (pronounced blurr-FULL) is a common (in some circles) word used when you cannot think of a specific example of what is being discussed. As in: "Joe, it's easy, you take the hammer and just tap the blurfl into place.", or "Hand me a philips screwdriver and the blurfl in the lower tray of my tool box." A humorous example in the wood working realm is here. Similar in use to a WIDGET in the land of programmers.
So, when I couldn't decide on a domain name, I chose blurfl. Rather witty I think. But hey, I'm easily amused.
...blurfl is not a slang place holder for a vulgar word, and it is not a derogatory adjective. I have a special key on my keyboard for those purposes.
Why doesn't this web address start with WWW? Because it drives me crazy that people think web sites have to start with WWW — so mine does not. That thing you type after http:// is called a hostname and they can be nearly anything. (eg, kids.blkbx.com.) Your web browser simply looks up the numerical Internet address for the hostname you typed (or clicked on) and connects to that system. The names are just for the humans and are truly meaningless.
...sigh. People see my domain name registered, go to www.blurfl.com, don't find a site, and then e-mail me to ask is this domain for sale? So, I had to make a boring site for www.blurfl.com — stupidity knows no bounds.