Hate it or love it, Adobe's (formerly Macromedia) Flash format has become almost de-facto on multimedia sites today, and is used for entertainment and decoration alike on the Internet. Flash web pages, flash games, flash presentations, flash kiosk portals, et cetera. And now, Flash celebrates it's 10th birthday. 10 full years of either seizure-inducing rotations of bright colors or effective web menus have given developers and software producers years to refine use of Flash, and often today we see it done quite professionally.
In fact, Flash is so prevalant that according to some statistics, 98% of Internet-connected users have Flash installed on their PC. Beat that, Microsoft. The article has a bit of interesting history on the development of flash, as well as some commentary from product manager Mike Downey, including what direction Adobe intends to take Flash. He also references the pending release of Flash 9 for Linux, and mobile applications for Flash. For good or for bad, Flash is moving ever forward. Maybe it'll make it to 20.