A number of years I built a spinnaker pole made cheaply from bamboo, as described earlier in this thread. Here's a bit of an update. The pole is
still going strong (with picture). It's been generally trouble free and I can't imagine ever wanting to switch this for a heavier and more expensive aluminum one.
That said, I did bang the pole against the forestay while sailing at the upper end of the wind range where I still fly the spinnaker and while on a broad reach - always the most challenging point of sail for a symmetric spinnaker.
This jarred loose one of the end fittings to where it could be wiggled a bit. So I re-seated it with a bit of Marine Tex and at the same time gave the end of the pole another wrap of fiberglass to strengthen it against that kind of wrenching, sideways load on the fitting.
Treating your pole like that isn't recommended, but it's good to see that it held up so well that I could still finish the sail that day.
PS: for reference, here is the post with the
description of how I put it together.