Lightweight poncho (was Re: [pct-l] Fabric from Stephenson)

[Tom Rogers" <tom-rogers@home.com (Tom Rogers)]

I just bought a 1.3 oz sil-nylon over the pack poncho from Campmor for $45,
(total weight 7 oz).  That beats Stephenson's by $20.  It's on page 169 of
the summer catalog, but not in the on-line store.  I can't make one for that
price.  The poncho will replace the gore-tex parka I've carried in the past.

Any specific recommendations for silicon product to seal the seam?  Someone
on this list mentioned a clear silicon bathtub caulk once????

Hobbit (3 weeks and counting for my southbound start)