The Gorillapod Mobile 3G. (iPhone 4 not out yet)
1. A case for my iPhone
2. A flexible tripod (stand to watch movie)
3. Free iPhone app (Gorillacam) for time-lapse, self-timer multiple shots ...)
4. In addition, there is an additional attachment with a standard screw for use of the tripod with other digital cameras. (Joby sells a bigger stand for the heavier SLR).
All these for just 35 SGD (26.20 USD). To me, this is one of the best add-on for the iPhone.