Universal Fence Clamps with Clamp-It™, Special Offer!
I saw this in "Ken's favorite shop tips" in The Family Handyman April 2014.
Tackle any mending job or woodworking project with these Specialty Clamp Tools. The Set of 2 90-Degree Clamps (7"W x 7"D x 1-1/2"H, each) works as adjustable co
3-Axis Welders Welding Angle Clamp - From a post all about welding clamps.
Clamping at ANY Angle
90 Degree Angle Fixturing Clamp Welding Plans
DIY Vise Clamp 90 Degree Corner Clamping Wood Work Bird House | eBay
Jig to assist 90 degree corner clamping.