Awesome

jquery.transform2d.js adds 2d transform capabilities to jQuery css() and animate() functions.

Usage:

Set transform with a string

$(elem).css('transform', 'translate(50px, 30px) rotate(25deg) scale(2,.5) skewX(-35deg)');
$(elem).animate({transform: 'translateY(-100px) rotate(1rad) scaleX(2) skewY(42deg)'});

You can use the following list of transform functions:

translateX(<number>px)
translateY(<number>px)
combined: translate(<number>px, <number>px) the second number is optional and defaults to 0
scaleX(<number>)
scaleY(<number>)
combined: scale(<number>, <number>) the second number is optional and defaults to the value of the first one
rotate(<angle>) units for angles are rad (default), deg or grad.
skewX(<angle>)
skewY(<angle>)
matrix(<number>, <number>, <number>, <number>, <number>, <number>)*

*matrix gives you more control about the resulting transformation, using a matrix construction set.
When using it in animations however, it makes it impossible to predict how the current and target transformations are going to be interpolated; there is no way to tell whether elements are going to rotate clockwise or anti-clockwise for instance.

Get transform

returns a computed transform matrix.

$(elem).css('transform') == 'matrix(0,1,-1,0,100,50)';

Relative animations

Relative animations are possible by prepending "+=" to the transform string.

$(elem).css('transform', 'rotate(45deg)');
// using the following syntax, elem will always rotate 90deg anticlockwise
$(elem).animate({transform: '+=rotate(-90deg)'});

Limitations:

requires jQuery 1.4.3+,
Should you use the translate property, then your elements need to be absolutely positionned in a relatively positionned wrapper or it will fail in IE,
transformOrigin is not accessible.

Why such restrictions with 'translate'?

Since translate is unavailable in IE<9, we have to emulate it using top and left properties of the element style.
This can, of course, only work if the elements are absolutely positionned in a relatively positionned wrapper.

Other plugins position the elements and wrap them transparently.
I think that transparently messing with the DOM often introduces unpredictible behavior.
Unpredictible behavior leads developpers to fear plugins.
Fear leads to anger. Anger leads to hate. Hate leads to suffering.
I prefer leaving this up to you.

License

Dual licensed under GPL and MIT licenses.