Duratrax's Onyx line of chargers have some great features compared to those chargers that only have a switch and some LEDs
I avoid shopping for non-robot parts such as batteries and chargers at robotic sites. Pretty much every robot site I have seen do not have good deals on batteries and chargers. Don't limit yourself to buying parts at just robot sites!
http://www3.towerhobbies.com/cgi-bin/WTI0095P?FVSEARCH=onyx+charger&search=Go