Change Cost Of Weapons
Backup the file before editing!!! It is possible to edit the INI.big file in your game directory. But you have to use a Hex-Editor.
Do not change the lenght of the file or the game will not boot again.
Just Overwrite the Text you need.
Example:
Search for "BuildCost" and overwrite it like
"BuildCost = 2000" Orig.
"BuildCost = 0000" Faked.
Do not DELETE anything.

Blow Up A Battalion Of Infantries
If you are the Chinese make at least 10 inferno tanks and send them all together at once and park them somewhere where your opponent love to send you those rebels or rangers or red guards to sneak on you and once they pass you you can watch the fireworks blow!!! inferno tank works great with their technology too!!! now you know how to beat those scums!
[note: this works too with the GLA toxic truck.]

Old Unit Names
Bring up the console and type in Russia:Yuri_Relived to get unit names from older C&C titles (No new graphics though)

How to win against turtling opponents
Well, tired of those online players that do nothing but build up there defenses? Well here's the solution! all you have to do is, if your usa, send raptors to eliminate there defenses and supply centers as necessary, try going for the power supply first, and use the A10 strike to weather down there defenses more. Then after there power and supply center is out they will have trouble knowing when you coming and creating new defenses. At this point simply send in a sizable force of humvees with the tow missile upgrade and full of rangers with capture building. Simply send them in unload the rangers and capture and sell there base.

Airfield Hint
When you are China, build an airfield and put a speaker tower right behind it. So when your planes have got damaged in battle they heal faster. To make it even quicker upgrade the speaker towers in the propaganda center