I'd say a Visa or Mastercard gift card so everyone can get something they want or can use.
I have cabinets full of coffee mugs, water bottles, hats, ski caps, scarves, hoodies, windbreakers and shirts that I have received over the years.
Only thing I really got that was cool was 5 years ago they gave us all HD flip cameras, but that cost them about $70 each, so above your price threshold.