Sometimes I just need a quick, mini-pack to grab and run. This comes in handy when I am not going on a long trip or have large work to produce in the field. It is super lightweight and, just like an emergency kit, I can always have it stocked and ready! Total weight is less than your 10 lb. sack of flour. Backpack/purse: Literally supposed to be used as a purse, this is super small and has no frills (like water bottle holders or inside pockets, etc.)
OpenBox M 8x10: As with all of their boxes, the 8x10 refers to the mixing area. I can paint anything up to 16" wide.
Slik Sprint Pro II Mini: A shorter version of the Slik Sprint Pro II, this tripod is super sturdy just like the larger. At only $67, it's a gotta-get! (NOTE: I am only 5'6" tall. If you are taller, and you stand to paint like I do, you may have to move up a stick to the Slik Sprint Pro II, not the mini.)
Minimal brushes: The Rosemary 8-piece set gets me by just fine.
Collapsible Umbrella by JudsonArt.
Basic paint set: Only need 3 colors (Cad Yellow Light, Napthol Red, Ultramarine Blue) and white to paint 97% of what comes my way. Notice in this pic that I have mixed secondaries from the three primaries to make paint mixing faster. The pile of warm neutral at the bottom is just where I cleaned off my palette knife after mixing the secondaries together. That other little clear pile bottom right is Gamblin, Solvent Free Gel.