I just picked up a container of Crest Liquid Gel and was able to transfer this material (without any problem) to one of my Bozeman Mountain Works (BMW) .35 oz bottles. The BMW bottles, which are available on the BPL site, are used by many of us to repackage many of our liquids including Aqua Mira, deet, hand sanitizer, and sunblock.
The BMW bottles can be squeezed and the liquid gel easily passes through the bottle's orifice to your toothbrush. Anyone considering using baking soda, or toothpaste now has an available alternative. Full BMW bottle weighs .4 oz.
Both Crest and Colgate have a wide assortment of flavors available if anyone wishes to try them.