As you might know, I have been bitten by the atc-bug and for these little cards you can never have enough interesting backgrounds. My friend and I made a couple of sheets using different techniques. The first two pictures show the result of different acrylic paints on gessoed watercolor paper. Stamps and punchinella (sequin waste) have been used to get interesting prints:
For the other two sheets we used procion dyes as ink on the same type of paper. Added some salt or sand to get interesting patterns. The first picture is done on plain watercolor paper:
The second one is done on gessoed watercolor paper. As you can see you get a more muted effect:
Even though the sheets of paper look very interesting like they are, they are even more interesting when cut up into atc-size.