For Nikon DSLR owners, the necessary interval shooting is via the built-in intervalometer in the D700 (and most other newer models I think--even my old D200 has this feature). Just set it and go away for an hour or so, the camera does it all for you automatically. This particular effort involved 600 photos (one every 5 seconds), but I only processed 400. I sat around for 50 minutes enjoying the view while the camera tripped along. Half an hour editing and rendering and there it was!
Here's a more recent effort, again using this software combination, and again a very low-res, bandwidth-friendly version. The original of this is amazing, the sun's rays rotating across the sky while the higher clouds move in the opposite direction. Again, it is full 1920 x 1080 HD, rendered at 30 frames per second:
Like I said, I'm missing 35mm film less and less these days.