Lightweight, no-frills, camera-specific, spherical pano-head for the Panasonic LX100.
Drawings in PDF format are posted here: http://1drv.ms/1K3cxqn Revision dates posted in the Readme.txt file.
Parts and material cost ~US$50 + a friend with a lathe and mill.
Part that mounts on camera stays on camera. Battery and SD card still accessible.