+++ on the FoodSaver. I have the small handheld rechargeable (~$20), works great.
I bought it about a year ago, and sealed some dry stuff (Frontier no-salt pizza seasoning, which is great for spaghetti); just recently opened it, had to use a churchkey can opener to break the seal.
But I only use it with regular canning jars because the plastic bags just don't seem to hold the seal very well. If you have the large machine FoodSaver and the jar sealer (they come in both regular & wide-mouth -- you can buy them separately), just set the handheld FoodSaver tip directly on top of the hole (no hose) in the center of the jar sealer, and press the trigger. If you have trouble with powdery materials, wipe the jar rim with a damp (not wet) paper towel and immediately set the tin lid on the rim and activate the sealer.
Foods suitable for this method:
Baking soda
Biscuit & pancake mixes
Bread crumbs
Candy
Cereals & dry oatmeal
Coconut oil
Cornmeal & muffin mix
Couscous, orzo, teff
Cream of Wheat (farina)
Dehydrated vegetables
Dry beans & legumes (a pint jar is usual amount for one pot of beans)
Dry instant mashed or scalloped potato mixes
Dry lentils, barley, quinoa, amaranth, millet
Dry soup mixes
Honey (it never goes bad)
Instant coffee, tea, cocoa mix
Jerky
Pasta
Pretzels
Dry popcorn kernels
Powdered milk
Raisins, banana chips & other dried fruits
Sunflower seeds
Seasonings, spices & soup mixes, incl. those little packets from Ramen soups
Tea bags
White rice, wild rice (brown rice has too much oil, will go rancid if not refrigerated)
White granulated, powdered & brown sugar will practically keep forever in jars, but you DO NOT want to suck the air out, or they turn into bricks. Just put a regular white plastic lid on it (the kind you use after you've opened canned food and want to refrigerate the leftovers).