A Scholar/Rogue

[YossarianLives]

I was thinking. Rogues are supposed to be skill monkeys. But they usually end up being a generic stealthy lockpicker.
How would it be if you played a rogue as something else. Maybe focusing entirely on charisma based skills. But what if you played a character focused entirely on intelligence based skills mainly knowledge. Do you think this would work? Could it contribute to the party?

[Catalysis]

Changeling Rogue racial substitution gets rid of trapfinding for sweet social ability (take 10 on bluff gather information intimidante sense motive, reduce time of gather info from 1d4+1 hours to 1d4+1 x 10 minutes, reduce gut assessement of a social situation from 1min (10 rounds) to 1 round (6sec))
On top of that, you have 10+int bonus skill points, and you add a knowledge of your choice to your class skill list (basic rogues only know knowledge (local)).

Would it be effective to find a way to master all knowledge?
Only if you are going for some kind of scout/recon unit, evaluating your foes' power from affar. Maybe, but be sure to take sense motive to evaluate their overall challenge rating.

Good luck!

-Catalysis

[VoxRationis]

Well, the rogue as it stands only has Knowledge (local), though you might be able to negotiate the matter with your DM. They do, however, get all the social interaction skills, as well as Disguise and Forgery, which basically means you're the Spy from TF2:
"Worst of all, he could be any one of us! He could be inside this very room! He could be you, he could be me, he could EVEN..."
Knowledge skills in general are quite useful, with or without the Knowledge Devotion feat everyone raves about. There are enough obscure abilities and immunities running about that it helps to be able to definitively say your character knows them without metagaming.
Incidentally, if you want a scholarly, skill-focused character and a true jack of all trades, look no further than the savant from Dragon Compendium, only mildly ridiculous. If the limited spell progression throws off the desired tone, consider the expert (either from the DMG or the generic expert from Unearthed Arcana).

[Azoth]

Throw Knowledge devotion on him and you can add another knowledge skill as a class skill and it will be useful in combat as well.

Also, you could take Educated feat at level 1 to make all knowledge skills class skills.

A 3 level dip in Swashbuckler will get you Int to damage with finessable weapons as well.

You could make a decent run for being a book worm and still be combat effective.

Human or Changeling Rogue3/swash3 with Daring Outlaw, Knowledge Devotion, and Educated seems a decent base for an Int based mele type that uses his knowledge to rip enemies apart. Prioritize Int/Dex/Con and go to town.

[Mountain]

Factotum at first level with the Able Learner feat gets you all skills as class skills for any class you ever take.

Knowledge Devotion is great for combat, if that's your thing.
Swashbuckler and warblade are useful dips for such a rogue, making more use of INT.

If a proper INT-based skill monkey is what you're going for, I can't say enough how much fun a factotum can be.