Screenshot showing the new "Investigate IP" page, useful for getting more information about an IP of a misbehaving user, etc.:

The idea is to provide the site administrator with tools to drill down and understand problem users.
And here's the complementary "Investigate User" page -- but only showing investigation info about the IPs found to be used by the user (a lot more info needs to be added to this page):

From these two pages you can cross reference information, finding all users who use certain ips, or finding all ips used by certain users, and then digging into the logs for details if you need to.