Name Voyager
Just come across this interesting visualisation of names. Shows the popularity of names from 1880 to 2005. It's a Java thingy you can launch from here - Name Voyager. BTW, the data is from the US census so not many Harry's now but plenty of Britney's a few years ago!
Note: difficulty in finding out exactly which names are the most popular is there is a lot on display, colour coding is obviously note the full solution here! Anyway, it's quite fun and slick.