Wipes...
Antibacterial wipes. I like the smaller cloth-like sample-sized packet. Easy to carry and easy to dispense.

Journal and crayons...
I always bring a journal and wonderful German crayons. They come in little, thin tins (for easy storage) that I buy at an art store. When you put a bit of water over your drawing, you get a water color effect. Take time to play!

Stuffsack...
I suggest you put all your daypack stuff into a "stuffsack" and secure it well. It will not only stay dryer in a rainstorm, it will also stay safer. Thieves who think about cutting your bag or trying to get in will have a much harder time reaching your essentials. Ed. note: An outdoor equipment shop would be the best place to find this item.

Dental floss...
Dental floss is extremely small, takes up no room and it's useful for many, many things. Think improvised washline, flying a kite, sewing your pack, and even cleaning your teeth.

Packtowels...
You've probably heard of these from other travellers, but I'm including it in my list because I never leave home without one. These towels are small, very absorbent and quick to dry. I found mine at a camping store. Regular towels are simply too bulky and they get stinky when you are forced to pack them when they're still damp.

Doorstop...
Carry a plastic doorstop. Stick it under your door anywhere (including your train compartment) and, of course, your hotel door (with an iffy lock) and no one will get in except Superman.

Bandaids...
I don't leave home without an assortment of bandaids - all shapes and sizes. I hope I don't need them but one never knows. Ed. Note: Cute guys (both young and old) very often need bandaids - it pays to keep your packet where they're always accessible.

Flashlight...
Carry a little flashlight plus, I always bring this bigger one made by Ever Ready (I believe). Go to the flashlight section of your department store. This model is yellow with kind of a flared out thing around the bulb area -- you can't miss it. It's small enough, it has a wider beam and it doubles as a lamp. You pull on the base and the middle becomes this nice, soft light that will be very welcome should the power go out, or in your tent, or if you just plain want to read and everyone else in your hostel room is sleeping. Cost: About $6.00 P.S. Always carry a spare bulb and batteries.

Safety pins...
A safety-pinned zipper is harder for a thief to open. Pin all your zippers to discourage casual rip-offs.

Cable lock...
Buy a combination cable lock. They're small, cost about $10 and they allow you to park your pack more readily. (i.e.) Lock your pack to the overhead holder on a train and go get a sandwich. Most thieves are just small time potatoes, they'll look for an easy-to-grab bag. I use my lock all the time. Tiny locks on the zippers are great too. Most casual thieves won't bother to cut your pack. You'll have peace of mind for only $10.

Silk sleepsack...
This item weighs almost nothing, takes no room, is warm or cool as it needs to be, is easy to wash, keeps between you and questionable bedding. Use it on a train, right in your sleeping bag or anywhere. They are the greatest!