Well, here's one more step down the road to running just EVERYthing with your phone.  onOne Software has developed a $10 application for remote-controlling your Canon DSLR with your iPhone or iPod.  Crazy.

With the Pro version you get remote adjustments, remote firing, image review, live view and even an intervalometer.  You can run it on these cameras:

- Digital Rebel XT, Rebel XTi, Rebel XS, Rebel XSi*
- 20D, 30D, 40D*, 50D*
- 5D, 5D Mark II* - 1D Mark II, Mark IIn, Mark III*
- 1Ds Mark II, Mark III*

The link to the onOne site, and DSLR Camera Remote is here.