The fuse block that Twisted Throttle sells has a sense wire you connect to a running light lead or such, so it knows when the bike is off. It also has a pigtail for a Battery Tender Plus, which will disconnect when you turn the key on to prevent the charger from pumping voltage in while the ECU is running.
I had one on my ZX14, and it worked great. It only does (+) so you have to run a ground wire up as well, or if all your stuff is low amperage, find a ground nearby and use that.
There is plenty of room on the right ram air tube (outside side) to tie-wrap it in place.
Also, Murph's Kits sells a fuse block which is very good.
I recommend this if you are going to hook up more than one thing, because hanging several farkles off a horn or running light wire is a recipe for overload, not to mention getting busy around the tap location.
Living the Gypsy Life