Larger creatures and whip reach.

[RangerWickett]

Normally, a reach weapon doubles your reach. A human with a glaive threatens foes 10 ft. away A troll with a large glaive threatens at 15 and 20 ft. away. An awakened Tarrasque with a colossal glaive threatens from 30 ft. to 50 ft.

A human with a whip doesn't threaten at all, but he can attack foes from 5 ft. to 15 ft. away. That's a tripling of his reach. What about a troll or a Tarrasque with whips of the appropriate size. Would a troll be able to use a whip against foes anywhere within 30 ft.? A Tarrasque against anyone within 75 ft.?

Sign me up for the awakened Tarrasque lasher with whirlwind attack. Then again, I suppose at character level 80+, you ought to be able to do crazy stuff like hit everyone within 75 ft. for 1d8+17. Wow, that's actually kinda weenie. Hrm.

 

[Flyspeck23]

A human with a whip doesn't threaten at all, but he can attack foes from 5 ft. to 15 ft. away. That's a tripling of his reach. What about a troll or a Tarrasque with whips of the appropriate size. Would a troll be able to use a whip against foes anywhere within 30 ft.? A Tarrasque against anyone within 75 ft.?

From the SRD:
"Reach Weapons: Glaives, guisarmes, lances, longspears, ranseurs, spiked chains, and whips are reach weapons. A reach weapon is a melee weapon that allows its wielder to strike at targets that aren’t adjacent to him or her. Most reach double the wielder’s natural reach, meaning that a typical Small or Medium wielder of such a weapon can attack a creature 10 feet away, but not a creature in an adjacent square. A typical Large character wielding a reach weapon of the appropriate size can attack a creature 15 or 20 feet away, but not adjacent creatures or creatures up to 10 feet away."
"Whip: A whip deals nonlethal damage. It deals no damage to any creature with an armor bonus of +1 or higher or a natural armor bonus of +3 or higher. The whip is treated as a melee weapon with 15-foot reach, though you don’t threaten the area into which you can make an attack. In addition, unlike most other weapons with reach, you can use it against foes anywhere within your reach (including adjacent foes)."

So I'd say yes, the normal reach is tripled - 30 ft. for the troll, 60 ft. for the tarrasque (why 75?) - although the description of the whip doesn't deal with whips of different sizes, nor does it say that it triples the reach. But that's what it does

 

[Shallown]

Sorry, an awakened Tarrasque with a spiked chain is much more scary. But yeah I would think it follows the normal reach rules. Whip just doesn't fit in as a melee or missile weapon. Its just too dang funky.

Later

 

[Darklone]

Awakened Tarrasque with Wizard level:
"Sorry, I'm more the intellectual guy..."

 

[Flyspeck23]

Awakened Tarrasque with Wizard level:
"Sorry, I'm more the intellectual guy..."

... and I'd really be sorry for that Tarrasque. Pumping up the CR with nearly no benefit whatsoever...

Tarrasque with bard levels... now that's a sign for sore eyes... or ears... whatever.