MyFishFinder.com Just like iceshanty but warmer
i went to the local dollar store and got some window and door alarms, they were only a dollar obviously, and they have a magnet that when moved away from the unit it make the most annoying loud squeal youve ever heard... simply hook the small magnet to the flag rod and your good to go....the plus side to a siren is that you dont have to look outside for a light constantly,but then again,if your fishing at night and your tip ups are close you will have to figure out what one is screaming.. the power to the unit cant be activated unless the magnet is removed..i bet you could hot wire the LED into that easy as pie.. if you want to see the set up i could post a pic,but i think i rambled on about it enough for ya to get the mental image
also -- for the power source, I was thinking about a double a battery... im not too fond of the watch batteries... that should be enough power right?
the sirens i was talking about are powered by 2 aaa batts... i never really use my tip ups so im not sure how many trips out in the cold they will handle but i used mine 3 times last year,for about 5 hours at least each time,and it still works... you owe me for getting up to check it,and the damn thing about made me have a heart-attack when i flipped the on switch,i wasnt actually expecting it to beller at me after sitting all summer.