On flash, we been using a GRADIENT MASKING action scripts for a fade in left to right, diagonal blocks and curtains slide show transition.
I’m amaze with the AviaSlider plugin of Jquery, a beautiful slide show transitions that capable of fade in/out, fade in any direction, diagonal blocks and curtains transition of images. Its also supported major browser, Firefox, Opera, Google Chrome and imagine its support Internet Explorer 6 to higher version. AviaSlider is also HTML5 ready.
AviaSlider is a very flexible and easy to use Image slideshow plugin for jQuery, it also comes with an image preloader so the slider starts when images are ready to be shown.
AviaSlides comes up with eight (8) unique transition effects, can supports linked images and taglines.