Gwar it's on Fileplanet now if you don't mind the wait. It's a short wait right now.
From their site:
Pre-RElease Multiplayer Demo
PRE-RELEASE MULTIPLAYER DEMO AVAILABLE NOW!
To receive a copy of the TRON 2.0 Multiplayer demo reserve your copy of the game at Electronics Boutique, GameStop or CompUSA or download demo at
www.nvidia.com or
www.fileplanet.com.
Please note that the TRON 2.0 Multiplayer Demo is a pre-release demo. Depending on your hardware, some players may experience minor issues that will be corrected in the final version of the game. The demo contains the single player light cycle tutorial, one single player light cycle circuit, one multiplayer light cycle map, and one multiplayer disc arena.
DEMO HINTS:
DISC ARENA/TOURNAMENT
1) When hosting a game, turn "Spectator Discs" ON which will enables combat in the lobby. Depending on the number of players in the game "Spectator Discs" ON may affect the performance of the game.
2) When you "rez-in" to the arena your disc will not be active. Type '1' then click the left mouse button to arm your disc. You only need to type "1" at the beginning for the first match.
3) Hit F1 to join a team. Click on the empty space "----". Your player name will appear in the space. Hit F1 to return to the lobby. When an arena becomes available you will be "rezzed" into combat.
4) Default keyboard commands:
W - forward
A - Strafe right
S - backward
D - Strafe left
C - crouch
Spacebar - jump
T - talk
Q - look around/lean left
E - look around/lean right
Left click - Fire
Right click - Block (when disc is in hand) or retrieve (disc already in flight)
Ctrl-LeftClick - backhand (melee attack)
Caps Lock - Toggle Walk
Z - Toggle Crouch
To steer the disc in-flight click and hold the left mouse button and drag in the direction you want the disc to arc.
MULTIPLAYER LIGHT CYCLES
Multiplayer light cycles are designed for LAN play. In the demo, Light Cycle racing over the Internet is an option but is only recommended for players with high end systems and really fast connections (DSL or T1). In LAN play you can have up to 8 player on the light cycle grid. On the Internet 2 to 4 players is recommend.
Keyboard commands (default):
W - accelerate
A - turn left
S - decelerate
D - turn right
; (semi-colon) - toggle camera lock (provides greater camera control)
' (apostrophe) - toggle 1st/3rd person mode
+ or - or mouse wheel - zoom in/out
Left click - activate power up (e.g.: turbo curse)
Mouse - Camera Control
For more information please see the README file on the demo. As always, please make sure you have the latest hardware drivers for your system.
I'm trying to get it from Fileplanet. Right now it's only a 5 minute wait,but then it's a 160 meg d/l