Your question is a bit vague but perhaps this might help
Natural Products -
Fruit and Trees (Donegal Apple-Pear, Kincha, Naranji)
Grain (New Avalon, Terra, or Shipely Wheats, Quillar)
Vegetables {Cholach (BT Potato), Dried Darkweed, Chava (BT Coffee)}, Herbs, and Spices (Medicinal or Culinary).
Useful Animals (Agrat, Brockway Goat, Berry Ants, Odessan Raxx, Tharkan Gazelle, Turin Horse, Tuktu, Tarise)
Frozen food (Blue Snapper, Jewel Bass, Sauget, and Ironfin Tuna filets, Denkaika Calamari, Grumium Clams, Hoyleton Forest Steer and Range-Bull Steaks)
Exotic Pets (Alrakis Tigerfalcon, Canopian Chihuaha, Khogs, Lesser Branth, Scarlet Shrike, Space Cats, Surats, Tariqs, Ghost Bears)
Invasive Species (Crana, some kind of Tubeworms that eat spaceship insulation, Grausian Bloodsuckers, Clamp Leechs, Vrikk)
Processed Products or Cultural Goods
Hardwoods (Kaumberg Oak Stocks, Titan Palm Posts)
Gemstones, Precious, or Rare Earth Metals, Jewelry or items made thereof
Dead Animals or their Parts (Kyotan Armor Bear, Rapier Fish, Crocale Hides, Bones, Ivory, Horns, Scales, Leathers, and Feathers), Jewelry or items made therof
Exotic Spirits
Designer and Mundane Clothing or Textiles
Medical Supplies
Fuel - Ammonia, Natural Gas, Petrol, Diesel, Denatured Alcohol, Cryogenic Hydrogen, Fuel Grade Fissile Material
Spare Parts - Nuclear (Fusion or Fission) Reactors, Fuel Cell Engines, Gyros, Thrusters, Limbs, Armor Panels, Base Structure, Myomer, Ammunition, Lift Equipment, Tracks, Tires, Rotors, Life Support, Sensors (Remote and Integrated)
Durable Goods
Small Arms,
Support Weapons,
Telecommunications Equipment (Fiber Optics, Radio Equipment, Microwave Transmitter, etc...),
Computers (Semiconductors, Sub-Assemblies, etc...),
Scientific Apparatus, Other Capital Goods/Industrial Machinery,
Light Support Vehicles (Bulldog, Pintel, etc...),
Exoskeletons/Power Armor,
Heavier Support Vehicles (Mech Recovery Vehicle, Engineering Vehicle, J-27, 135-Ks, MASH, Artillery Gun Carriers),
Combat Vehicles, Aircraft, Battlemechs, IndustrialMechs
Illicit/Contraband/Gray Market Goods
Fancy Drugs (Brace, Quikstim, X-Quick, Rage, Spazz, LD-512, K-Z, Can-Do)
Regular Drugs
Banned Media (Whether for your own good or the state's depends)
Assassin's Weapons (Radium Sniper Rifle)
Forged Documents
Stolen Secrets (Civil, Scientific, Military, Intelligence, past or present)
Non-Military Lostech (like Stasis Tubes or parts for Terraforming equipment) or ClanTech (smuggled in from the Dark Caste)
'Recovered' Cybernetics (Particularly BlakeTech)
Scientific 'Experiments' (Genetically Engineered Organisms, DNA or other Biologicals from People or other things, Bio/Chemical Weapons) and Poisons
Weapons Grade Fissile Material