Column Selection is in beta2 along with elapsed time.
Screenshot:
http://traxel.com/img/lumbermill.png
Coming in beta 1 (the next release, probably in a few hours); elapsed time between arbitrary events.
Screenshot:
http://traxel.com/img/lumbermill-elapsed.png
There's a screenshot of 2.0 available here: http://traxel.com/img/lumbermill.png
The single most requested feature from my coworkers is a client mill that will allow us to connect to our servers. This has been implemented in alpha 7. It's compatible with Log4J's SocketHubAppender. JSR47 doesn't come with a server (AFAIK), so I'll be writing one (it's worth trying Log4J if you haven't, and don't mind the extra jar - it really is better).