If somebody would be upset that you took it then isn't it stealing rather than scrounging? Just what my parents taught me and I teach my kids, but eveybody had to draw their own line I suppose.
My current bargains:
Swill army knife, you can pick up a new knife with two knife blades, can opener/screwdriver bottle opener screwdriver and a wonderful fit and finish for $10-15. Insanely useful, utterly reliable.
Dorcy AAA LED flaslight, this is new to me, but I'm very impressed so far, for $5 at wally world you get a nice bright EDC light that's almost so cheap as to be disposable.
Virgin mobile pay as you go phone, this is only a bargain if you are a very very seldom phone user. I call my wife on mine maybe every two weeks when I'm out and I need to ask her something. She's the only one who has my number and calls me about as often. You need to put $20 every 90 days on it and I never use that up. So it costs me $6.66 a month for an emergency phone. Good option for me since I live in the houston metro area and signal is great.
Those are my current 'bargains'