I'm looking for a particular EQ...

Not too sure where to post this, figured I'd have the better chance in here, since it's the busiest section... so, I'm searching for an EQ plug-in that allows you to bring your whole curve up or down once you're done adjusting your parameters. Anyone knows of such an EQ?

DMG Audio EQuality.  http://dmgaudio.com/products_equality.php
 
And this isn't a sales pitch, exactly, but the plug-in does what you're asking and then some. It's just what I use. I'm thoroughly impressed with them.

Voxengo's CurveEQ: http://www.voxengo.com/product/curveeq/

@scook right, but that's not really what I'm looking for... this will change the properties of my curve as I move all the nodes up or down, it doesn't keep the overall curve. also no way to keep horizontal position locked in...
 
@sharke the way I would like to do it, is use eq boosting at first to shape my tones, then once that's done, bring the overall curve down so my highest point is equal to neutral and then raise track volume, as all eqs are considerably better at cutting than boosting. would be more convenient that way, I believe, than trying to do my curve by cutting only.
 
gonna try the demos of some of these suggestions, cheers lads.

brconflict
DMG Audio EQuality.  http://dmgaudio.com/products_equality.php
 
And this isn't a sales pitch, exactly, but the plug-in does what you're asking and then some. It's just what I use. I'm thoroughly impressed with them.

+1 for DMG Eq's.

What you're describing is basically a gain control within the eq, but with differences. The eq would have to intelligently re-map a new set of filters to do that. For example a simple high shelf boost of 3dB brought down 1dB would intelligently need to convert that to a 1dB low shelf cut with a 2dB high shelf gain. The thing is, you might not be able to recreate the same opposite curve exactly with more complex filters, but I may be wrong. I do get what you're asking, but I can't imagine many designers going through the effort of doing that. It is an interesting concept. My guess is anything out there would simply just use a gain change instead of an intelligent algorithm (which probably wouldn't actually be too hard to engineer) which defeats the whole purpose of cutting only. It really complicates the eq design.

I wonder though. A simple peak at 1khz uses one filter. To invert that, you'd now need TWO filters to achieve the same result. Do the total artifacts add up to be the same in the end or even worse? I'm curious.

I must do some cut vs boost experiments...

Although its not what you are looking for you may want to try GlissEQ from Voxengo. 

Yes but that will simply be a gain change, not reconstructing the filters to create an identical response. Different process. Wether the sound is any different between the two is another matter. But in some eqs it may well be - especially in ones modeling analogue.