This is the skeleton of my Wifi Water (Mt. Dew) Bottle project. It provides airflow and mounting for a battery and a Raspberry Pi.
Parts:
The bottom of the bottle can be cut away and then it pressure fits in to the base.
This version is in a single piece, but could be two pieces in a future version. I've found that printing it on its side, which does require a lot of support, gives the skeleton better protection from the battery and Pi rocking and breaking the mounting point.
Pontential future enhancements:
1. Multiple parts that mechanically connect.
2. Relief gaps in the base to allow for the bottle to push in without cracking the base.
The author marked this model as their own original creation.