I'll admit that I'm slightly obsessed with zoomooz.js, it's a cross-browser (excluding IE) nice zoom plugin for jQuery. And although it has some issues with scrolling it's a top-notch plugin in my books. To showcase it's greatness I made a mock-up of a picture gallery*:
*if any of the pictures are yours let me know and I'll acknowledge you here.
Update: A good intro on Zoomooz.js can be found here.