My 3d printed "Video Skate Dolly" is a handy piece of gear to add to your collection. It has an adjustable arm, rotating base, and tilting head. The wheels can also be adjusted to shoot a 360 degree video. Using recycled roller-blade wheels and PLA plastic it is easy on the environment and your budget.
Sample video shot with the Video Skate Dolly is at http://www.engineeringwithjazz.com/
http://youtu.be/wLvJfAjgkNI
http://youtu.be/wC0j3efGzcc

Full instructions at http://www.instructables.com/id/Video-Skate-Dolly/
Print all parts at 33%+ to prevent flexing and add stability. All nuts and bolts are 1/4"-20 thread.
Required hardware:
3 rubber washers
11 nuts
4 at 1-1/2" bolts for wheels
4 at 1" bolts for rail and arm
2 at 1-1/4" bolts
1 at 2" bolt for camera head
1 at 3/4" bolts to attach to camera