The $30 PVC Shoulder Mounted Camera Stabilizer.

After a few trial and error runs, this is one of my designs for a simple stabilizer that can be built for less than $30 (considering one already has the tools required).  It provides excellent vertical as well as horizontal stability.  Most of the other designs seemed not get as good of results when viewed.  Also serves as an excellent mounting platform for accessories.  All off the shelf parts, nothing custom.