It turns out that the Wi-Fi menu in Mac OS X Leopard (that's right-- Leopard, not Snow Leopard) has some hidden super-powers.
 
I didn't notice them until yesterday, the day before Leopard was officially made obsolete by Apple's release of its snowy cousin (tip 'o the hat to Glenn Fleishmann, http://tr.im/xobg).
 
If you hold down the option key and select the Wi-Fi menu, you can see more information about the particular Wi-Fi network that you're associated with.

Here's what the extra information means:
 
AP MAC address: the wireless MAC address of the device you're associated with. It will (usually) have a wired MAC address too, which is typically off by 1 digit. (And that's the MAC address we use to identify the AP in SputnikNet).
 
Wi-Fi channel: shows the channel of the signal (1-11, though generally speaking there are only 3 truly discreet channels, 1, 6 and 11).
 
RSSI or Received Signal Strength Indicator: shows the signal strength. Apple's scale (which is vendor-specific) varies from 0 (good) to -100 (bad). Not sure whether Apple's scale is linear (probably more understandable by end users) or logarithmic (more realistic, as the inverse square law applies to how radio frequencies propagate in free space).
 
Transmit Rate: shows the data transfer rate in Mbit/s, in this case 54 Mbit/s, the theoretical maximum net bit rate of 802.11g.
 
But wait, there's more! If you hold down the option key, select an an alternate Wi-Fi access point and hold, you can get a bit more information about it, too...

In this case, you get both RSSI information and the security method.
 
Snow Leopard adds several new features... I'll document those as soon as I update. But for those who plan on using Leopard for a while, it provides some useful (if rather well hidden) Wi-Fi information.

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