keyboard - Is there a USB power consumption meter?

For example, how could I measure the normal power consumption of my USB keyboard?

After I get my statistics, I may easily notice when a hardware keylogger gets installed, by the changed power consumption.

Answer

USB current/voltage meters exist. Here's one on Amazon (though unfortunately out of stock at the moment). Here's the same model on eBay (from Germany, but ships worldwide).

Alternatively, if you're up for a bit of DIY, see this project on Instructables. You'll need a multimeter, though, because that's just a passive passthrough connector that simply provides a couple of test points.