Rebecca sends me to What's special about this number, a total delight. And the first entry, under √-1,1 reminds me that I meant to thank the BBC's In Our Time podcast on negative numbers, a few weeks back, for enlightening me about a road near where I live over in ScienceLand. Via. G. Cardano commemorates the man who discovered i. Not a lot of people know that. For even more juicy tidbits, including wonderful stuff about renaissance mathematical competitions, you'll have to dig up the podcast.
And then, I wondered whether Gardner would have found hyperlinks and computers useful for his sort of thing, and I wondered whether he was still alive, and I searched and searched and became very frustrated that I never did act on my brilliant idea of some years back to start a web site called "Are they dead" and then I came across Dead People Server and I am grateful to Laurie D.T. Mann who informed me that the old guy (born 1914) is still alive.3