Some call it a bathroom bag, toiletries, ditty bag, or overnight gear--I call it the traditional name, a dopp kit.
Mine is specifically designed to have everything I should need for long motorcycle trips or up to one month in a foreign country [two events i am planning for this fall].
Starting with the bag, I chose leather for its durability and style. I also decided on one with extra side pockets instead of the traditional central zipper style.
The major groups/bags inside
Beside my bag are a few loose items and below that are four major bags. Being an engineer, I organized my items by function and reduced the size of everything. There are some items I use every time I open my bag and others once a week.
Toothbag: used two or three times a day
Morning bathroom bag: used only in the morning
Shave/Eye bag: used every few days
Loose in bag:
The main bag's top flap has a zippered enclosure which contains two small ziplock bags.
Mini-Medkit: for most basic health issues