ASP.NET RImageOrFlashControl makes it possible to show a picture or a flash on your web-page depending on the file type.

If a file extension is swf, then <object> tag corresponding to the flash, or <img> will be rendered on the page. Likewise, using the properties of this control you can establish all the parameters necessary to show your flash.

100% .NET Managed Code Doesn't require installation Supports all .NET languages Easy to use possible to use in Web applications Features: automatically determines the file type

allows to establish all necessary parameters for the flash

Also: Free to use (freeware) Free support FREE updates (including major version upgrades)