$ host paulgraham.com
paulgraham.com has address 68.142.205.137
paulgraham.com has address 216.252.126.190
paulgraham.com mail is handled by 10 milter1.store.vip.mud.yahoo.com.
paulgraham.com mail is handled by 10 milter1.store.vip.sp1.yahoo.com.
$ host 68.142.205.137
137.205.142.68.in-addr.arpa domain name pointer html1.store.vip.mud.yahoo.com.
$ host 216.252.126.190
190.126.252.216.in-addr.arpa domain name pointer html1.store.vip.sp1.yahoo.com.
I remember pg saying in a comment or article somewhere that his site was one of the few remaining sites still running on the old viaweb system (presumably the one written in lisp).
According to a more recent post, Yahoo! forced Paul to move to the C++ version in the Fall; he experienced some side effects, from what I remember reading.