Most of us charge our laptop batteries by simply plugging in our laptops, but there are times when you need to have a spare battery or two ready to go at a moment's notice.

For Mac users, accessory maker FastMac now has a universal Apple laptop battery charger, called the U-Charge (imagine the lawsuit if they tried to call it "iCharge"), that connects to a pretty huge list of current and classic Apple laptop batteries.

The US$69 battery charger includes several different adapters for connecting to your Apple battery, and while it's not available just yet, FastMac expects to ship these within the next 30 days. At the moment it's available in US and European plugs (the latter attracting a US$1.99 surcharge), however FastMac will ship internationally and it should work just fine in Australia if you pick up a cheap converter.

Pretty cool idea overall, but will this just give MacBook Air critics another reason to knock that system for not having a removable battery?

The compatible Apple laptop batteries are as follows:

• iBook G3 12-inch
• iBook G4 12-inch
• MacBook 13-inch
• MacBook Pro 15-inch
• MacBook Pro 17-inch
• PowerBook G3 Bronze (Lombard)
• PowerBook G3 Pismo
• PowerBook G4 12-inch
• PowerBook G4 15-inch
• PowerBook G4 17-inch