In terms of specific stuff, this is what I buy week after week (your mileage may vary):
WW bread or deli thins (1 pp per slice breads are basically 90 calories or less per 2-slice serving, though if you get a Points Plus Calculator, this can vary between brands)
Propel Zero flavored water (it's non-carbonated, so it's essentially just H2O)
Nutrigrain bars (the best 3 pp that I can carry with me anywhere)
Bananas!!!!! (free fruit!)
Buddig or other light lunchmeats
2% milk cheese slices
Fettucine Alfredo and Santa Fe Beans and Rice WW entrees
Orange juice to freeze in 3/4 cup servings (2 pp and tastes like gelato)
precooked taco meat (Chi-Chi's) and low-carb tortillas
Diet iced tea
94% fat-free popcorn
broccoli and cauliflower (fresh or frozen)
fat-free salsa (no sugar added, chunky style)
shredded cheese (for flavoring in small amounts)
WW pita breads
heart-healthy pasta sauce (the last 3 items make a nice pizza for 3-4 points each with onions and peppers)
Everybody eventually finds the stuff that satisfies them, which makes those foods a "bargain" for that person. Pre-cooked taco meat is one of these for me. Three PP per half-cup, and there's all kinds of things that you can do with it, not just tacos. With a teaspoon of ketchup, it makes a great sloppy joe to eat open-faced on deli thins. A cup of taco meat on a green salad is a great entree for a total of 6 points (7 if you add some cheese).
While on the topic of PP bargains, am I the only person who buys an extra chili or two when I go to Wendy's and put them in the freezer? 4 PP for a small chili is an insane points bargain, especially for fast food. My essential 11-point fast food lunch is: Wendy's junior hamburger deluxe with no mayo (6), chili (4), garden salad with fat-free French dressing (1), diet lemonade (0).
I was gone but now I'm back!