As K3n said OBW and stack and whack are the same process. Kaleidoscope refers to the affect you get when you cut the same spot in the fabric and sew them into blocks.
A Kaleidoscope can be any shape you want to use. They can be one patch as in the OBW or they can be cut in triangles or Dresden petal shapes.
The biggest differance is when you cut them in a triangle or Dresden shape they are sewn together and appliqued onto a background and sashing is usually used between blocks. The OBW are sewn together making a sort of a one patch quilt top. No applique or sashing.
I have a Dresden Kaleidoscope EBook available that I wrote. I just like the look of the Dresden Kaleidoscopes. It combines the idea of the Kaleidoscope with the shape of a Dresden Plate quilt block.
It is just two differant techniques to enjoy the same basic look.
It is all in what you like. I sent K3n some of my Dresdens so she could see what I do and she made me a little One Block Woofer quilt that has dogs in the fabric hence the Woofer name! She asked me to choose among 3 names for her quilt and I didn't know she was also making me alittle one! So I chose the Woofer name! I thought it was so much fun at the time but didn't know I was getting one!