May I suggest Firefox?
Object: To rearrange the puzzle pieces into the correct order in less than three minutes. Each triangle on a puzzle piece must match up to the color on the piece placed next to it on all sides, save for triangle on the edge.
How to Play: Click and drag any puzzle piece over another puzzle piece to swap positions with it. If the piece is dropped in the correct spot, it will animate (expect in Opera and versions of Safari less than 1.2 - consider that additional difficulty) by fading out and back in. Click the "Quick Look" button to see a brief preview of what the puzzle should look like when completely put together.