SLIGHT SPLURGE
Saje Parisian Garden soap bar:
Used as a facial cleanser with a soft bristled cleansing brush with a travel case to prevent crushing of the bristles. It cuts down on liquid components and not overly perfumy. The French green clay ingredient is soothing for oily skin. It's slightly pricey for a bar of soap but lasts a long time as a facial cleaner.
STEALS
Coconut oil:
Used as a makeup removal and universal moisturizer. It stays as a solid below 24 C (76 F) so I melt mine with beeswax at home to thicken it up. It's especially good for removing eye makeup without potential of eye irritation and much cheaper than commercial preparations. Buy a jar for home and refill in travel container as needed.
Crystal deodorant:
No perfumes and the one thing I found that doesn't irritate my arm pit skin after a particularly bad episode with regular stick antiperspirants on a hiking trip. Only problem is finding a compact one for travel that doesn't weigh much. The sticks last forever. I ended up rotating my home, gym and travel sticks after several months to get a small one for travel.
Peppermint essential oil:
A small 15ml bottle is easy enough to carry. A few drops to any shampoo to will give you a pleasant tingly scalp and a refreshing feeling after a long travel day. Do not apply undiluted to sensitive areas and be careful not to wipe your shampoo-infused hands over your face while in the shower (it became UNpleasantly tingly on face but was great on scalp).