I've accidentally plugged in the balance leads backwards, you won't get them in all the way, but you'll get them close enough to create a nice POW and a black mark on your tap.

I think parallel boards without fuses or circuitry that monitors voltages before making contact are a bad idea.  First, the balancer connectors we use are OK for other uses where connecting them backwards is benign, but are a bad design for the parallel board application.  I color-coded my board so I wouldn't get a balance connector backward, and I am careful not to connect batteries at different states of charge, but I still toasted a trace.  Do something less dangerous while you talk on the phone-- like driving a car. 

Oh yeah, I'm a big advocate of fused parrallel chraging boards like the Revoelctrix MPA

http://www.revolectrix.com/MPA_XH.htm

I also like the fact that the max transfer rate between packs is fuse limited to 40 amps, which is something to consider if you inadvertently plug in a fresh pack and a drained one. The packs will instantaneously try and level their voltage, and you may end up having a massive current go through the leads, but with the fuses, you'll more than likely blow a fuse before you blow a pack.


Also, as an aside, I think that most of the balance connections are a little too solid, in that they can be hard to remove, and you may end up bending your fingernails backwards trying to get them off (yeowch!)

I taken to using these neat little connector protectors, which give you more meat to grip and look fairly tidy too.

http://hobbyking.com/hobbyking/store/__19943__Balance_Plug_Savers_JST_XH_6s_5pc_Per_Bag_.html

These are 6s ones (the first ones I found) but you can get them in any size you like.

These days I've pretty much realised that I'm a massive dumbass, and whatever I can do (buy borrow or make) to ensure that my dumbassery is foiled at every turn, I do. I have far less problems this way than thinking I'm better than that 

Didnt the phone work as a camera . ?