First of all, a siamese fighter is a betta, and unless you're keeping a sorority or breeding, this is not possible,
gouramis are another no-no as they are a member of the same family and will attack each other.
Tetras and barbs might be ok as long as they aren't too fast, or too flashy, or have longer fins, or are nippy
Livebearers is usually bad, but some people find that they can get along with female guppies and dull platies. I wouldn't reccomend male guppys or swords because they have longer fins, and guppy males are flashy. If you are keeping them with livebearers you should keep a plan on what to do if they fight (have a tank set up etc...)
corys are usually ok, but with all fish, it all depends on the betta's temperament.