IMC, Free Orcs are Klingons. Here's their stats:
Free Orc
Medium size
Base Speed 30 ft.
Str +2, Dex -2
Weapon Familiarity: Free Orcs treat Orcish Double-Axes as Martial rather than Exotic weapons.
+4 racial bonus on saving throws against poison
+2 racial bonus on Spot checks
+2 racial bonus on Survival checks
Darkvision (Ex): Orcs can see in the dark up to 60 feet. Darkvision is black and white only, but it is otherwise like normal sight, and orcs can function just fine with no light at all.
Automatic Languages: Common and Orc.
Bonus Languages: Draconic, Dwarven, Elven, Giant, Goblin, and Gnome.
Favored Class: Barbarian.
... and the famous "Orc Double-Axe" is in fact that funky Klingon slashing weapon. I'm sure that Klingons were based on Orcs, but the Klingon evolved into a playable race, while the Orc stayed "stereotyped".
-- N
PS: Also, it gives the Orc language a whole new dimension. Everyone knows that Elvish has a dictionary, now Orcs can use the Klingon dictionary.