Except for the radar cheat, all these work in multi-player mode.

Undocumented key codes:

Total Annihilation Keyboard Commands

Taken from the support site...

ESC Cancels the current command before it is executed
1-9 Select the menu for the current unit
, (comma) Select the previous menu for that unit
. (period) Select the next menu for that unit
~ (tilde) Toggle damage bars on the units
PAUSE Pause the game
SHIFT Hold down to queue up multiple commands
ENTER Activate the message bar
TAB Multi-Player specific options
F1 Display information on selected unit
F2 Toggle Options menu
F3 Go to the unit that last reported/chatted information
F4 Lists kills, losses, player name and colors
F5-F7 Map bookmarks
F8 Captures "movie" of gameplay (toggles on/off)
F9 Screen capture (will Print screen to file SHOT####.pcx)
F11 Switch modes (normal to debug)
F12 Clear all chat messages
CTRL+A Select all units
CTRL+B Selects all builders
CTRL+C Select and center on Commander
CTRL+D Self-destruct selected units (toggles on/off)
CTRL+S Select all units in current view
CTRL+V Selects all aircraft
CTRL+Z Select all units of same type
CTRL1 - CTRL9 Assign the currently selected units to a squad
ALT1 - ALT9 Activate (select) the previously assigned squad
A Give an attack order
B Select the Build menu for that unit
C Give a capture order
D Use the Disintegrator Gun
E Give a reclaim order
F Toggles advanced AI (hold fire/return fire/fire at will)
G Give a guard order
H Share resources with another player (allies)
M Give a move order
N Scroll to the next unit off screen
O Select the Order menu for the current unit
P Give a patrol order
R Give a repair order
S Give a stop order (cancel any previous orders)
T Track the selected unit
V Toggles advanced AI (hold position/maneuver/roam)
- Reduce the game speed
+ Increase the game speed