I was reading this at Smashing Magazine (great blog) and thought about passing it on.

#1) Splash pages display disclaimers or warnings which are supposed to restrict access to content such as pornography, advertising, or gambling (as is required by law).
#2) It is necessary to draw visitors’ attention to an important message such as approaching deadline, critical update, latest release, news, slogan etc.
#3) Visitors are supposed to select the language they want to use or the country they come from — to direct users to the appropriate version of the site.
#4) Visitors can choose between a low-bandwidth version (HTML — Dial-Up) and high-bandwidth version (Flash — cable, DSL). Sometimes one can also choose the “accessible” version containing only text without images.
#5) The designer informs visitors about site requirements such as used browsers, screen resolution as well as used Flash, Java, Quicktime etc. and suggests to choose the “right” configuration and download plug-ins for “optimal” site presentation.
#6) Visitors can select the preferred view mode – for instance, standard mode and fullscreen mode.
#7) Multiples sites share the same domain. Or a large site tries to communicate its most important sections directly.
#8) Splash page is supposed to include hints for browsing the site and explains the main sections.
#9) Designers use splash page trying to awake excitement for the actual content of the site.
#10) Sound is announced. Visitors are asked to turn on their loudspeakers to enjoy the Flash-show or Midi-experience (yes, apparently Midis are still alive).
#11) Splash pages are used as an additional form of advertising.
#12) The decision to use a splash page is design-driven and realizes some designer’s idea.