I initially had it explained to me as a term used for any materials that are textured through the use of steam so that is what I think shibori is, but I reckon that is slightly different- if you know more then please leave a comment. :D
So I thought I would show you some before and after pictures just so you get kind of an idea of the things you can do with shibori and marbles etc.
This one I pleated then wrapped elastic bands round to get a sort of double whammy- as I would end up with the pleats being fixed and also the tension of the bands.
This one began as two layers of organza, one yellow and one pink (yellow on the top which is what gives it the slightly peachy colour) with big marbles!!
...which didn't really look that special, and the bits that I had scrunched weren't textured enough for me so I started stitching into it, adding pleats and little circles and just generally going mad with the sewing machine, until I ended up with....
Incidentally, I have come across quite an interesting shibori artist called Michelle Griffiths who has done the most amazing things and is well worth a look at!