Comment 24 for bug 894943

My full support. But!:
If it's possible, it's not good to "share" something, be it power, money, etc. The reasons can be read above. Instead, make something much simpler and much more efficient and straightforward: change owner for (donate) objects.
This way, you can give energy by donating a powerplant; give money by the means of a miner/refinery; tech by a tech/Factory building, so on. This way we're not straying away from the default game. Plus you can give units/infantry.
Nevertheless, it wouldn't be too much of strategy if the allies had each other's tech tree. Well, then make it so you could only give units/inf (my opinion). Past this point, sharing energy, tech, is not strategy-wise.
The prism/tesla thing is pretty neat.
For a full customization, a tag like IsDonable= can be made for builds/units/inf

Anyway, I play multiplayer 80% and it'd be more enjoyable with this feature. It's a must.