Allow me to correct a few things I think are wrong

> fastawdtsi's diagram is useful when explaing drift in a hover and
> hence why this discussion began.

This is assuming he tries to hold the main disk LEVEL. To hover he would need to be a little bit rolled so that the RIGHT is a bit lower (assuming a CW rotor; CW as seen from the top of the heli; tail rotor is pulling to left as in fastawdtsi's diagram)

> Use a couple clicks of trim to null it out in a hover.

You can NOT trim this out. You FLY this out by shortly applying a little bit of right roll

About Eric's problem of left BANK problem. It seems to me the same effect but now with changing forces. If you turn right the tail has to be pulled to the left, hence the tail rotor pushes left harder, causing left bank. To correct it you would need to roll the heli to the right a bit. This becomes tricky because you can not just roll to the left with the same amount after the turn to become stable again -- your heli has turned so that what was a left roll after the turn appears to be maybe a little bit of downpitch.
To illustrate this, consider a sudden 90deg turn right while hovering. After the turn your heli will be accelerating (1) forward: the right side of the heli was down before the turn, so after the turn the front side of the heli is down (2) to the left: assuming the heli was not pitching down (with the nose) before the turn, after the turn the heli will not be rolled a little bit to the right anymore and the tail rotor will push the heli to the left.

Docster, about the gyroscopic precession effect of the left-pushing tail.. I think you're nearly right, only the nose will go UP with right turn instead of down. More tail force to the left will cause a force downwards on the right side of the rotor disk, and on CW rotors this results in pitch UP. This might partially correct for acceleration (1) mentioned above, if these forces are carefully balanced in the design.

EVSCOTT
> Hell this problem will probably
> dissapear once I get into actual forward flight!

With forward flight you will get additional problems due to different airspeeds of the forward going and retreating blade, causing increased force on the left side of the disk (CW rotor) resulting in pitch-up tendency. Some people try to trim this out - of course the problem then returns in the hover. Others claim that the flapping head is solving this - I dont see that right now...

ADAMB
> real heli's pitch slightly forward and
> slightly right cyclic to maintain hover to counteract all the forces
> involved with spinning rotors...

I dont think that forward cyclic is required for this. As far as I know real helis have their rotor slanted forward because of other reasons such as efficiency in forward flight.

BTW the original question was a beginner's issue, but this roll due to tail force certainly is not. For additional discussion on this I think the question general discussion forum would be the right place, probably with a link to this thread.