You can open a lot of 3ds files together.
You can scale and rotate the 3ds-objects.
You can walk around and inside the 3ds-objects.
Simply use 4 arrow buttons for rotate or walk around the object.
Use "plus" and "minus" buttons on numpad for scale the object.
Use "Man" button on toolbar for switching "walk" or "look" mode.

Usefull Keyboard buttons:

Home - for look from start (home) point (also 5 on numpad)
+ - on numpad for more zoom (zoom in)
- - on numpad for less zoom (zoom out)
R - autorotate the object (on / off)
W - white background (on / off)
N - coordinate net (on / off)
A - coordinate axies (on / off)
9 - on numpad for increase rotation speed
3 - on numpad for decrease rotation speed

"Look" mode:

Left arrow - rotate the scene to left
Right arrow - rotate the scene to right
Up arrow - rotate the scene forwards.
Down arrow - rotate the scene backwards.

"Walk" mode:

Left arrow - turn to left (also 4 on numpad)
Right arrow - turn to right (also 6 on numpad)
Up arrow - go forward.
Down arrow - go back.
Shift + Left arrow - shift to left
Shift + Right arrow - shift to right
Shift + Up arrow - rise upwards (also Page Up)
Shift + Down arrow - lowered downwards (also Page Down )
Ctrl + Shift + Arrows - move slowly.
Ctrl + Up arrow - bend forward (also 8 on numpad)
Ctrl + Down arrow - bend backward (also 2 on numpad)
F2 - look forward.

You can use VIViewer for viewing "single" 3ds files, without additional files (textures etc).
For acceleration of walking, representation of 3ds files is lowered.

For registration run VIViewer and enter User Name and Serial Number in Menu Help / Registration.

Operating System requirement: WinME, WinXP, Windows2000, Windows2003