You can't do much with an IP address. It could be the IP address of a Tor exit node.
No else because theymos confirmed that Satoshi Nakamoto always used Tor during his active time in the forum and Bitcoin community.
I'll probably release Satoshi's PMs and logged IPs addresses in ~8 years. This'd probably be of great historical interest. (Though he always used Tor, as far as I can tell.)
2021 edit: I changed my mind: I am not going to release Satoshi's PMs in 2021. See my post
here.