Here are some snacks I like...I think they are all pretty healthy. Of course it depends if you're trying to lose weight, I would avoid the carbs.
Popcorn, if you make it yourself (not using the bags filled with gobs of goo).
Also you can do a lot with peanut butter, which is healthy if you use natural kinds (avoid partially hydrogenated oils like the plague). Spread it on crackers, celery, etc. You can make a peanut butter banana sandwich.
Vermont Cabot Extra sharp cheddar is good with just about anything, such as apples or crackers. These two are also a good combination in a sandwich.
I also like English muffins with jam.
Cottage cheese is another nice snack. Try it mixed with peach slices, or with maple syrup drizzled on top.
Make your own trail mix with raisins, almonds (excellent source of protein), chex and stuff.
Cinnamon and applesauce. Vanilla yogurt.
Real guacamole dip with chips, or chunky salsa
Some good teas...like vanilla chai tea and Rooibos. Drink with milk and real honey