Several years ago I purchased a bag of 50 very small bright color balloons to try something. I put just a small amount of air in it and squeezed the air to the tip so that the inflated ball was about 3/8" in diameter. Then I attached tying thread(in a bobbin) and wrapped it tightly right at the base of the inflated ball. Made a lot of wraps by flipping the bobbin at the juncture just created. I tyed off with several 1/2 hitches and cut the thread. Then I cut the excess below the juncture but left slightly more than 1/16" of a 'butt' remaining. This 'butt' helps to keep the tippet or leader in place. Applied head cement to the wraps.

When it comes time to use this, make a knot in the leader or tippet. I don't know the name of the knot but it has 2 loops. You can also use a slip knot or any other knot that will work. Place the knot between the balloon and the butt then tighten.

Now, for the most part, I usually use a piece of yarn as an indicator/bobber because I hardly use weighted flies. However, if you do, this is a really good 'indicator/bobber'. The material is easy to get(try DollarTree), it's easy make and it's very inexpensive.

Allan