For me, the trickiest part of one-bag living is getting all the liquids and gels I want into that darned baggie. This is especially true when I'm going to be on the road and traveling for a few weeks. I know, I know, I could just buy stuff there and toss it while traveling. But I'm picky about my health-and-beauty aids, and I travel a lot to China, where buying toothpaste and cosmetics can be a chemical-roulette game. So I'd rather have things I know work well for me.
I found this brilliant idea on how to use plastic straws to contain viscous liquids and gels. DIY Travel Size Toiletries in Drinking Straws**| Mighty Girl And, since I already have a heat-sealer for making freezer packs with our garden produce, I figured all I would be out is a packet of straws if it didn't work.
But it did! And because they're so compact, they let you save plenty of space in the 3-1-1 baggie. Now, they won't work for very thin liquids, but for creamy stuff, they're super. (I tried them for hand cream, sunscreen, and a retinoid cream--all a success.) I clipped the end of the packet with nail clippers when I wanted to use the whole packet at one go, and used the pinhole trick for stuff I wanted to last for a few uses.