Personally, I am always looking for fun, creative things to make out of my old blue jean scraps. The denim material is good for many art projects. I have found this to be a very unique use for it. It's very easy, and it's very inexpensive if you have scissors, hot glue, and a pair of jeans.
I have the steps written out below, and I also have step-by-step pictures above.
The first step is the most tedious: cutting the pieces to make the coasters.
Take your pair of blue jeans and cut the hemlines out of your jeans. Smooth edges make the neatest looking coasters.
Next, grab your hot glue gun or fabric glue and begin wrapping the hem around itself.
Your coaster should be at least three and a quarter inches wide.
In order to get this width, continue you to glue hems together until you reach your desired width.
The third step is optional. Choose a fringe of some sort if you would like. I chose a brown, heavy duty twine that I had in my art box, but you could use ribbon, colored paper, pip cleaners, or pretty much anything else that will fit around the edge of your coasters.
The fourth step is to clean up any messiness. Hot glue can leave strings, and the denim can have straggly strings attached to it. Also, when you set your coaster down, it may not be completely flat. These are easy to fix problems.
Simply cut the extra strings off of the denim and glue, and use an iron to flatten them. The iron will only work if you used hot glue. But be careful what surface you do this on. You wouldn't want to melt anything with the hot glue.
I also used a lighter to burn off some excess denim, but that's not necessary.
The last step is simply to continue on to make the next coaster. My set has a total of 5 coasters, but you could make more or fewer.