I haven't really experimented with fat bombs, and I think the meltiness would be an issue for me. My on-the-go snack items are:
Tiny Tupperware tub of pate, spoon (I've got a very small tub for filling at home from supplies in the fridge)
One of those mini Philadelphia tubs, spoon.
Awfully Posh Pork Scratchings (expensive, but less risk of tooth cracking than other brands in my very real agonising experience)
Mini Peperami (or full size, depending on hunger levels)
Mini Babybel or Cheestring
And my favourite..... a hardboiled egg, served with an individual sachet of FF Hellman's. Squirt, bite, squirt, bite, nom nom nom........