I used to be a fan of NetworkMonitor until I saw a new software out today in VersionTracker: MenuMeters. This one easily take the crown! Very pretty and simple.

Right next to MenuMeters, I use Spy, Stuffit Deluxe, and the rest...

Post yours here. I don't care if it's boring but I'm sure people would love to see how you organize your menu bar. Clock at the beginning of left or right, Sound at middle, ... ?