Blue Cat DP Meter Pro

It's a very nice meter, covers all the bases and normally sells for $79, so the sale price represents a 30% discount.
 
The unique capability of this one is that you can record measured levels as automation or MIDI. I've tried that, though, and found it to be a bit clumsy and non-intuitive. I had to consult the tutorial to make it work. The histogram feature is much more useful.
 
An even better deal: Voxengo SPAN does most of the same metering stuff such as K scales and correlation meter, and it's free. Add MMultiAnalyzer for $40 (current sale price) to get the histogram capability plus the ability to monitor multiple channels at once. 

The MMultiAnalyzer is pretty awesome.  I bought it without even a trial and put it to work immediately on some projects that I needed to remix this week.  Big help.