I see maxamps and hobbyking are selling flat life packs -

9.9v 4500 packs:

$180 from maxamps
$40 from hobbyking

http://www.maxamps.com/categories.php?cat=223

http://hobbyking.com/hobbycity/store...8&ParentCat=85


Have not tried them myself and won't be paying that much for a maxamps pack, but for $40 I may just want to try a pack from hobbyking.