Why aren't there any ads or other info snippets on loading screens of Flash-heavy websites? It's a huge missed opportunity since people actually look at these screens so that they don't miss the a-ha! moment, but are utterly bored and would be grateful for some entertainment. For an inspiration, play some video games. The Sims and Sim City franchises keep people smiling with cute pseudo-scientific nonsense such as the blurb below informing players that the game is "mitigating time-stream discontinuities".
It's a lot like that business case legend about a company that had just built a major building realized their elevators were intolerably slow and installed mirrors to cut the perceived wait time.