Flash, javascript, plinky plonk sounds and adverts etc
We rarely use any of these distracting items

Who really wants to visit a site which :

takes minutes to download

half the punters can't see without downloading some kind of viewer or patch

gives different results depending on screen resolution and size

gives different results depending on which browser is used

clutters up your design with unwanted, unsolicited promotions, just for a few pence

surely a website is built to provide information, not demonstrate the esoteric skills of the misgudied programmer

there are odd occasions when these things can't be avoided

so unless you are Disney we suggest you leave well alone ...

here is a list of why not

# Flash doesn't work everywhere, unlike normal HTML. My computer runs a 64-bit OS without 32bit emulation, and Adobe has yet to provide a Flash player for any 64-bit platform.
# Flash requires a proprietary plugin.
# Flash does not let users change font sizes or contrast settings using personalized stylesheets.
# A lot of screenreaders and other accessibility tools does not work with Flash (some screenreaders does using a Windows-specific API).
# Flash is not indexable by all search engines. Some does index text in Flash files, but since there is no way to link to the subpage your query was found in, people can't be redirected to the result, making the result useless for users.
# If a browser doesn't support Flash, you get nothing unless the entire website is also saved in a standard compliant (also know as HTML) way. If a browser doesn't support CSS, you will still get a readable website.
# Flash doesn't not present my usual OS widgets (textfields, submit buttons and such) or use my OS settings for these (larger fontsizes, higher contrast and such).
# Flash is owned by a commercial entity and even though the format specification is open, it is not licensed for free use.
# Flash sites breaks the back button, a fundamental function that users are used to.
# There is no way to bookmark a subpage of most Flash-only sites.
# Flash doesn't work in most alternative browser devices, like PDAs or Smart phones.
# Printing content from a Flash site is extremely difficult and most of the time comes out weird on paper, if at all.