Down to 97 characters. Works for arbitrary graphs, i think. 
sub b {
$a=@_*@_;for(@_){%t=@_;$t=@r=$_;$t+=%t while@r=map@{delete$t{$_}},@r;$
+a=$t,$b=$_ if!ref&&$t<$a}$b
}

[download]

Update: Thanks to MeowChow for crawling through that thoroughly fetid blob of code and discovering that I need to say $t+=keys%t instead of $t+=%t. And here I thought I was being so clever.

In reply to Re: (Golf) Minimizing the Bacon Number by no_slogan
in thread (Golf) Minimizing the Bacon Number by Masem

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