<p>Okay, I guess this is entirely subjective and whatnot, but I was thinking about entropy sources for random number generators. It goes that most generators are seeded with the current time, correct? Well, I was curious as to what other sources could be used to generate perfectly valid, random (The loose definition) numbers.</p>

<p>Would using multiple sources (Such as time + current HDD seek time [We're being fantastical here]) together create a "more random" number than a single source? What are the logical limits of the amount of sources? How much is really enough? Is the time chosen simply because it is convenient?</p>

<p>Excuse me if this sort of thing is not allowed, but I'm curious as to the theory behind the sources.</p>

Don't worry about a "good" seed for a random number generator.  The statistical properties of the sequence do not depend on how the generator is seeded.  There are other things, however. to worry about.  See
Pitfalls in Random Number Generation
.
As for hardware random number generators, these physical sources have to be measured, and the measurement process has systematic errors. You might find "pseudo" random numbers to have higher quality than "real" random numbers.