Central Dust Collection - Dust Collection Tips, Jigs and Fixtures | WoodArchivist.com
Use a wye fitting rather than a tee so that less suck is required to move dust.
Chris Billman's Dust Collection Hoods
Dust Collection Plans - by David Grimes @ LumberJocks.com ~ woodworking community
Rather than a short radius 90 degree turn, incorporate two 45 degree bends with a section of straight pipe in the middle, which will allow the particles to scream right through the turn.
Woodworking Projects | Adding A Pre-Separator To Your Dust Collection System @ Woodworking News
Clear ducting for dust collection system. - brilliant
Downdraft Sanding Table Box - Learn how to make a simple box that will give you excellent dust collection for sanding your woodworking projects. FixThisBuildThat.com
DIY Cyclone Dust Collector - Dust Collection Tips, Jigs and Fixtures | WoodArchivist.com
Conquering the final frontier of dust collection for stationary belt sander