How about, "I'm Joe and I make $200,000 a year"? or; "I'm Joe and I drive a 2011 Lexus"?

If someone needs to be that specific about themselves, people are right to wonder about that person's motives. There is information we have about ourselves that's not supposed to be secret, but it is considered private- no the first thing you say aloud at a party.

Context is important here too: A mensa board is unlikely to take offense with an IQ comment. If you talk about your interest in DeviantArt, people might want you to be even more specific. A geneology board is a good place to talk about one's ancestry.

In each case, it's people's interpretation of Joe's social ability that we are reacting to, not just what he's saying.