I guess the limitations of Discourse are also for general stylistic reasons. Avoiding arbitrary fonts, colors, images that break out of the bounds of a single post, etc., were probably deliberate design considerations in order to keep the appearance of posts a bit more uniform and consistent with the format and expectations of a forum. However, for April Fools’ Day, I was tempted to request on meta.discourse.org for adding support for the <blink> tag.
@ginger2008, the formatting on this forum only supports a very limited subset of HTML, and most things can and should be most easily accomplished using Discourse’s specific dialect of Markdown.
Here is a thread that goes into using these forums in much more detail: