How to "middle-click" on new macbooks

Check out BetterTouchTool. It adds gestures to your trackpad or Magic Mouse and there's tons of gestures available to set actions to.

To add the functionality you're looking for choose »Trackpad« from the input dropdown and add »Three finger click« as trigger and »CMD+Click« as assigned action. Now clicking with three fingers will open it in a new tab.

For Safari you'll have to activate »⌘+click opens a link in a new tab«, before it works as intended.

ps. You can also set it to trigger with »Three finger tap«, but I can only get it to trigger consistently when I the »Force tab«, which I for one can't do consistently.

I don't believe its configurable within the OS, but MiddleClick, gives you a 3-tap middle click. Works really well in Firefox, which is what it was originally designed for. You'll need to tweak it so it fires up on logon.

If you use Firefox, Command-Click will open in a new tab.

Or you can hold two fingers on the trackpad and click; this gives you a right-click. You could then select 'open in new tab' from the context menu. (or get an extension like Tab Mix Plus and make right-click open a new tab)

what I want is a command-shift-click [...] I found the source code here: http://www.r0ssar00.com/2008/12/middle-click-on-mac-code.html... Could anyone out there pleeease add a few lines and compile it so it command-shift-clicks?

I've fixed/modified the code to, I think, perform a Cmd+shift+click (if not, try other values for (CGKeyCode)56 - but 56 seems to be shift)

// click.m
//
// Compile with: 
// gcc -o click click.m -framework ApplicationServices -framework Foundation
//
// Usage:
// ./click
// Will cmd+shift+click mouse at current location.
//
// Based on http://www.r0ssar00.com/2008/12/middle-click-on-mac-code.html
// For http://superuser.com/questions/13351/how-to-middle-click-on-new-macbooks/13356#13356
// Modified by dbr - http://neverfear.org


#import <Foundation/Foundation.h>
#import <ApplicationServices/ApplicationServices.h>


int main(int argc, char *argv[]) {
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
    NSUserDefaults *args = [NSUserDefaults standardUserDefaults];

    CGEventRef ourEvent = CGEventCreate(NULL);
    CGPoint ourLoc = CGEventGetLocation(ourEvent);

    CGPostKeyboardEvent((CGCharCode)0, (CGKeyCode)55, true); // Cmd
    CGPostKeyboardEvent((CGCharCode)0, (CGKeyCode)56, true); // Shift
    CGPostMouseEvent(ourLoc, 1, 1, 1);
    CGPostMouseEvent(ourLoc, 1, 1, 0);


    [pool release];
    return 0;
}

Combined with the technique mentioned in the link you mentioned (wrap the command in a Java app, and use MultiClutch), it should do it..

Jitouch allows you to set gestures, one of which is middle-click.