Clean monitoring menu bar, all open-source

What it looks like:



From left to right:

• CPU temperature: smcFanControl - options: temperature only
• Graphics switching: gfxCardStatus - options: default
• Network traffic: MenuMeters - options: throughput, receive/transmit, transmit = black@30%, receive = black@0%, inactive = black@33%
• CPU load by cores: MenuMeters - options: thermometer, user = black@40%, system = black@0%
• The rest is comes standard in OS X

All three (smcFanControl, gfxCardStatus, MenuMeters) are simple .app, no external daemon, open-source and free. smcFanControl is the only one of the bunch that requires root privilege for the fan control part but it seems safe -- at least it's not an opaque black box, see below.

Very happy with this setup .

The alternative is iStat Menus, which seems ideal on paper. Except that it:

• runs a daemon with permanent root privilege
• its daemon isn't CPU-efficient (I don't have the numbers off the top of my head, but I remember it was never idle)
• is closed-source
• costs $16