Easy Way to Obtain a Lot of Prestige:
This is a moderately long process to help you build up a lot of prestige. 
Play the game as normal, making sure you get every bit of prestige from every 
level. Once you have reached the point right before you have to fight Deja Vu 
at the university, you will need to make a custom character. At this point you 
should have about 17-18K prestige. I was able to make a customer character, 
Target, with 10 in all his stats and some really nifty attributes (blitzkrieg,
 crack shot, flier, light speed and tough guy). There is a wide range of 
powers to choose from, but the most potent I found is a double uppercut with 
high damage, low to medium knock back and enable "up knock back." 

Eliminate all of the enemies on the level before going for the replicator ray. 
Once you have taken out the bad guys and destroyed the replicator ray Deja Vu 
will appear and start multiplying. Take his health points down to about 50% 
and then take out his clones (you will know the difference because his psycho 
clones only have half of his health points). Follow him around eliminating his 
clones as they appear. He will continue to clone until you take him out. 
400 XP per clone. I worked my way up to about 74 clones (30,000 XP) before I 
accidentaly knocked him out. Do this, save and then you can make a character 
even more powerful than the one you just made! 

Console Mode:
(submitted by: Løne Wølf)
To enable the console mode, go to the Freedom Force/System folder and look for
the file name: Init.py 

Open the file with notepad or wordpad and type:
import ff
ff.CON_ENABLE=1 

(CON_ENABLE are all in capital letters) 

Now, you can open the console in the game at any time by pressing the 
tilde(~) key. You can also gain information about the frame rate by 
pressing "U". 

During the game, you can use these cheats (they are case sensitive): 

god() - God mode for all heroes
peace() - not sure what it does, although the enemies don't attack much...
DEBUG_ALLPOWERS=1 - gain all the abilities of the heroes in the game 
(note: ONLY for that particular mission!) 

These codes can be used only in the base (case sensitive too):
Campaign_AddPrestige(#)
Campaign_AddCP('name',#)
Campaign_Recruit('name')
Campaign_UnlockOrigin('name') 

# - numbers eg: 6000
name - name of heroes in lower case eg: Minute Man = minute_man
Mentor = mentor 

65K Prestige Points:
Hexedit your save game; go to locations 1068 1069 106C 106D. Change the values 
to FF. You now have 65k prestige points. There is a method to modify the .hero 
save files to change hero stats, but the prestige is figured dynamically, so 
there is no point.