1970 Topps #600 -- Willie Mays
Of course, I really don't need to give much of an introduction to who Willie Mays is.
I noticed something neat about this card...it's #600, which is very much in line with the way Topps gave card numbers divisible by 100 to the biggest superstars. However, Willie Mays had finished the 1969 season with exactly 600 career home runs. While that seems like a nice bit of synergy, check this out: my wantlist for 1970 Topps now stands at 60 cards in all. That means I have 660 cards from the set, which is the same number of home runs Mays had when he retired in 1973.
The first one was likely set up by Topps to tip a hat to Willie Mays. The second fact is quite a coincidence. It's one of those things that only a "numbers" guy -- like many of us collectors tend to be -- can appreciate.