The following skills are all ideas for skills - or modifications and cascades of existing skills - that I've added to the game system. They can be used or disregarded at referee's discretion.
Animal Husbandry
This is the zoological equivalent of farming. The ability to raise and breed animals. Like "Farming", it's handled in the abstract - a character with Animal Husbandry will have the ability, at referee's discretion, to breed herd animals and successfully raise them for whatever purposes.
Canine Handling / Training
More than just playing "fetch" - this is the ability to get dogs to do and (at higher levels) learn to do useful things - guarding, tracking, herding and the like. Go here for details.
Communications
The ability to make radios and telephones work, and knowing how to contact friendly forces (or eavesdrop on enemy communications), work around interference, and counter jamming. Go here for details.
Culinary / Food Handling
At lower levels, the ability to cook, handle and preserve food safely and efficiently. Also spills over into things like distilling alcohol for fuel, trade and recreation. Go here for details.
Medical (Proposed Changes)
Medicine is a broad field, with many specialties. I propose dividing the field into three different sub-skills. Go here for details.
Musician
The ability to play a musical instrument (or otherwise perform music). Go here for details.
Nuclear Reactor Operator
This allows the character to operate, as the name suggests, a nuclear reactor. I'm not sure how much explanation is needed or (given that I'm not, myself, a nuclear reactor operator) possible.
Seamanship
Handling oceangoing ships, and handling them on the open ocean. Go here for details.
Veterinary
The Medical (Veterinary) skill allows the character to diagnose, treat, and perform surgery on animals.
It cascades with "Medical (Diagnostic / Therapeutic) for humans at a 2/1 ratio; a veterinarian can often figure out what's wrong with a human, too.