French researcher Emmanuel Beaurepaire and colleagues have employed new microscope technology to capture the first 10 cell divisions of a zebrafish in early stages of development (Source). The technique relies on non-linear optical properties of a cell's membrane and microtubules to capture thousands of still images, which are then organized in sequence to resemble a movie.
The video above shows the process of zebrafish development from one cell to the 512-cell stage. The scale bar represents 100 micrometres. The embryo in the video is not labeled with any dyes, however soon enough fluorescent molecular markers will be combined with this approach and allow for more detailed visualization of early development.