I'm a doctor, not a mechanic
The "floater fan" is essentially a powerful, vertical wind tunnel that will blow an object that enters it upward. It is quite easy to implement and is an interesting alternative to a lift, kicker, or teleporter.
Implementation in UT2003
To make the floater fan "blow" actors around, you must make a physics volume in the shape of the area you want to be affected by the fan. This area can be as large or as small as you like, but generally a roughly cylindrical shape extending from the origin of the "fan" effect. (usually the fan itself) Then, set the gravity in the volume to an appropriate setting based on the power and facing of the fan. You can set a terminalvelocity if you want a more precise exit velocity, otherwise the exit velocity will generally depend on the entrance velocity and the length of time spent in the wind tunnel.
You will also probrably want to add a visual effect for the wind tunnel. This can be done by using a static mesh of a duct opening or a static mesh or mesh of an actual fan blade, with an appropriate rotation and physics type applied to it. To give more of an impression of the power of the fan you can add an emitter with bits of dust and whatnot coming out to make a visual "wind" effect.
Implementation in Unreal or Unreal Tournament
Similar to the UT2003 implementation, this is made instead by zoning off the area that the floater fan should affect. The ZoneGravity and TerminalVelocity settings of the new zone's ZoneInfo can then be set appropriately. ZoneVelocity can be used instead of ZoneGravity to make a more precise exit velocity.
To make a visual effect for the wind tunnel you will generally use a decoration, though a BSP-based "grate" could also suffice if that is your preference. Again, if it is a fan blade decoration you will likely want to make it rotate to get the best effect.
Category:Legacy To Do – Provide links to this page from appropriate places. Make into more of a tutorial.