back when i only had 2 controllers, i used to use the side port on my TV, worked great - always had one charging.
now i have the energizer 2 controller stand for my 3 dualshocks (2 always charging!) and a Dreamgear 4 port Move charger for my move controllers and navcon. I think both also have ports for usb cables to charge even more stuff, but i don't need to.
since we're talking controllers, I also HIGHLY recommend the trigger extensions (sold at best buy). Once you use them, the core Dual Shock triggers feel completely inadequate. So worth it.
I also dig the little anaog grip nubs from madcat. not quite as essential as the trigger extensions, but still nice (except they fall off just a bit too much, depending on game type -- they stay on fine for most games, but dual stick shooters get them to fall off).
anyway. point is, a dualshock with triggers and analog grips is amazing. absolutely amazing. well worth the investment to upgrade.