Are you looking for snacks that are more portable and won't spoil, or are you looking for snacks that don't require a knife and fork so they can be eaten on the road?
Personally, I like canned fish and beef jerky. I buy the low sodium canned fish which only has tuna and water(no added "stuff"). I also make my own beef jerky. It's actually pretty easy. I think Mark has a recipe somewhere on this site.
Also, canned vegetables won't go bad on you. There are varieties that only include vegetables and water. That way, you won't get any added chemicals.
For hands free snacking, I would suggest fruit or even cut up vegetables. I'm starting to see more and more gas stations carry little snack packs of fruit and vegetables. If you tolerate dairy, string cheese and wedge cheese can also be a good option which doesn't require a knife and fork.
I'm not sure if I know of anything that could help keep one awake besides for coffee. Getting a good nights sleep and eating proper food is the best way. But if you're getting sluggish on the road, then perhaps the fruit I mentioned might give you an extra "boost"? What about coconut water?