Imagine my surprise when I found out this little gem was not common knowledge!
Choose a module, for this example I used the very popular 425mm AutoCannon II, click on the Variations tab and then down the bottom select the Compare button.
Another screen will appear with the various versions of the module and some display options on the left hand side, select some of them.
Now we have the various versions of the 425mm AutoCannon showing their usage of power, CPU, etc etc.
Pretty damn useful if you ask me, much better than clicking back and forward to try and compare whatever statistic is the most important at the time.