I get a $10 every few months as a casual "thanks" from work, usually to Subway. I usually get a meal, then give whatever's left on the card to another guy in the office, who likes eating there quite a bit. That seems to buy a lot of goodwill, considering it's only $3-$4 left usually.
I also get bigger cards a few times a year from work, usually $50-$100 and I can choose from a set of stores (through our company's automated "thank you" system, I could also pick from a range of useless household gadgets). I usually pick a department store like Macy's or Kohls and put it towards a few new shirts. I wear an odd size dress shirt and live in a blue collar town, so not a lot of used clothing options here.