The Gadget: Newertech's MacBook and MacBook Pro Battery Charging Station, which let you charge and condition laptop batteries without having to swap out the one in your laptop.
The Verdict: Great build quality, fast charging, and overall convenience makes the price a non-factor when you need to charge multiple batteries simultaneously.
It actually charges only one battery at a time, but holds onto two so it can charge the second one in series after the first one's done.
The Performance: Charging took around the same time as a standard charge in our MacBook Pro (when not in use). Conditioning takes all night, but actually added a couple percentage points to our batteries (judged from CoconutBattery). If you put two drained batteries in when you go to sleep, they'll be done by the time you wake up.
The Price: $149 for all types of Mac laptops (MacBook, MacBook Pro 15/17, PowerBooks, iBooks)
The Recommendation: If you have the need to carry and use multiple batteries in the same day, pick up this charging station. If you've only got one battery, you can accomplish the conditioning yourself on your own laptop by carefully charging and draining your battery.