Increase production by spending gold.

[Ajuga]

I usually build some late cities yet their production is really slow even with me buying the production buildings. Sometimes I just want that happiness building that still takes 10 turns to be build in just a few turns less. Maybe I'm racing for a wonder and 1 or 2 turns could make all the difference yet focusing on production is not enough.
Or maybe I have an enemy invading me right at the doorstep and want to boost my production enough to get out 2 extra units.

How about being able to spend about 'x' gold per turn to get 'y' extra hammer in that city. (Three gold per turn for one hammer seems balanced enough.)
It would be a toggle in the city which sacrifices your total gold income in order to 'purchase' extra manpower. You could spend just 3 gold per turn but also 30 gold per turn to really boost the production in that specific city.

I would say that it should unlock at Guilds.

Like it? Dislike it?

 

[Strategia]

While I like the idea, and agree with the reasoning behind it, it could cause some problems in actual gameplay. It could lead to money becoming even more important than it is already, and from what I understand it's already valued more highly than raw production. Furthermore, this would essentially allow you to buy wonders, which is more than a little problematic. A civ with lots of money can already easily get ahead of comparable civs that don't have as much gold, simply by buying what they need instead of waiting for it. If this also applies to wonders, you've created a sort of doublewin mechanic, as players who already have a fairly big advantage can get even further ahead by buying wonders as well. Production would become comparatively meaningless in comparison to the all-powerful gold, especially since production buildings tend to have at least average maintenance costs, and I've seen some players say that they never bother to build Windmills, Nuclear Power Plants, or even Workshops because of that. What I'd rather see is some sort of boost to actual production, such as reducing the maintenance costs on production buildings, adding more production-boosting tile improvements like Civ4's Workshop or perhaps bringing back the idea of the Labourer "specialist".

p.s. there's no tech called Guilds in Civ5, although I could see this being attached to e.g. Machinery or Replaceable Parts.

 

[Ajuga]

I get your point, also the tech Guilds is in GAK.