I could have sworn I'd seen one of these too, but I can't find it now so I'll contribute. Having people state what apps they're running would make this a lot more worthwhile.
From left to right: Adium, Shimo, Quicksilver, Sync services (I can't get this to go away since I upgraded to Leopard, very annoying), Spaces, iStat menus (network, hard disk activity, memory usage, CPU usage x2), Bluetooth, WiFi, Input, Volume, Magical, and of course Spotlight.