No. Character entities (©, and such) are permitted, though.
If you want to know how to write good ALT texts without markup, please see Alan Flavell’s essay on choosing ALT texts.
Use server-side includes, if your server supports them. Ask your Webmaster if this is the case, and if so, what the exact syntax is for your server.
Since server-side includes make the document slower, they are not always desirable. If your documents only have a static footer, which doesn’t change every day, you might be better off by using an editor which can insert files in the current document, or a preprocessor. The C preprocessor can do this, but there are also several HTML-specific preprocessors available.
This script has two big problems. One, usually it uses the decrement operator (c–) at some ball. The “–” sequence in a comment actually closes it on some browsers, so your code may “leak” on those browsers. The same goes for “>”.
Second, keep in mind that many people consider this even worse than <BLINK>, and that it also suppresses the status information which normally appears there. It prevents people from knowing where a link goes to.
You can’t. The source is necessary for the browser to display your document. You have to send the complete, unencrypted source to the browser. Even if a particular browser doesn’t have a “View source” option, there are many that do, and you can always retrieve the document by hand (using telnet) to get its source. Or check the browser’s cache.
You can of course put a few hundred empty lines above the actual source, then newbies who don’t see the scrollbars will think there is nothing there.
There was a proposal in the now-expired HTML 3 draft to handle exactly this: just add SRC to the <HR> or <UL> tag, indicating where the image can be found. But until this is more widely supported, you have to use <IMG> for the rule, with a lot of “–” characters as ALT text for text browsers, and using a <DL> with only <DD> tags for each item. Make sure you use ALIGN for the image, which should go at the beginning of the item, of course. This isn’t as beautiful as a “real” list.
An alternative is using a two column table, with the bullets in the left column, and the text in the right. But this won’t work well on non-table supporting browsers.