I'd like a variable differential gravity field that pulls on different parts with different intensities. It's be a great stretching massage as long as one avoids the Roche Limit (http://en.wikipedia.org/wiki/Roche_limit).

I suspect that part of Apple's restrictive software distribution strategy is to avoid malware and crapware from creeping into the iPhone ecosystem. It's something like a walled garden or customs & border protection model for software distribution. Although I'm sure that enterprising criminals will find ways to break into the iPhone, Apple's approach does raise barriers to drive-by downloads, worms, trojans, and socially-engineered installations of malware.

Time will tell whether restricting software distribution for the iPhone is a net positive or negative in either creating a stable, easy-to-use, secure environment for mobile computing or in stifling development for a subset of developers.