My legal name is "Daniel" but I've always been a "Danny". This is a reasonably common name, but I've never had a major namespace collision before. (A family friend, who lived with us for a while when she was fifteen, was "Danielle" and at Sydney Uni I worked with a "Dan".)
But my sister's mother-in-law is a Danielle who is always called "Dani". And now there's a colleague of Camilla's — and a neighbour, since he's bought the house three down from us — who is also a "Danny". Both of these have already resulted in confusions.
Children should clearly be given globally unique names, trademarked as personal identifiers in all major jurisdictions...
In the broader world, I was once (a decade or so ago) among the top results on a Google search for "danny" — I used to joke that I was on first name terms with the Web — but have now (19th September 2010) been pushed to 12th (the exact results may vary with geographical location).
At the top of the results are a rapper and a footballer who I've never heard of, but who are public figures with high profile Wikipedia entries. Then there's Choo (a Japanese culture expert), Turver (a 19 year old with a MySpace profile), Ayers (a blogger who's had an online presence as long as I have), Ferguson (a blogger), Pang (a Hong Kong actor with an IMDB entry), Jones (a twitter feed), Noriega (another actor), and Sullivan (who blogs about search engines, and has also been around forever).
It says something about the prominence of social networking that otherwise unremarkable Twitter and MySpace pages now rank so highly in search results!