Shadowrun has some pretty cool corporations I use:
Saeder-Krupp Heavy Industries: Railguns, Power-plants and shipyards.
Wuxing Incorporated: Fire Controls and Sensors
Renraku Computer Systems: Fire Controls and Sensors
Shiawase Corporation: Lasers, Shields, and Jump-Drives
Ares Macrotechnology: Lasers, Railguns, Gauss Canons and shipyards.
Cross-Applies Technologies: Shields, Sensors,and Lasers
I also like using real and semi-real companies:
Lockheed-Boeing Aeronautics: Engines and shipyards
Rolls Royce Intergalactic: Engines and shipyards
BEA Systems: Beam point-defense and CIWS
Mitsubishi-Sugo (Actually from Cyberpunk): Engines and shipyards
Raytheon: Sensors, Fire Controls
I wish there was a way to store corp names and which technologies to apply them to so they'd appear automatically.
I'd like some more ideas since the US and Japan are over-represented IMO. Perhaps TaTa but I don't really know that they do outside of engines and I don't think they'd compete with Boeing an such.
Fictional mergers (Like Lockheed-Boeing) and fictional Space subsidiaries (Rolls Royce Intergalactic) of existing companies are my favorite, so if anyone has any ideas about that feel free to PM me so I can write them down.