Raw HTML With Snippet in WYSIWYG Editor

Does anyone know of a Raw Html snippet plugin that lets you call your snippets something other than numbers, has a "thingie" (not sure what they're called) in the WYSIWYG editor, and isn't buggie?

I have one that does everything other than let you name the snippets something that makes sense. It also seems to be a bit buggy - it sometimes shows ads and sometimes doesn't.

I need this for adsense ads. I use different ad placecment and size depending on what's on the page. For example, a page with affiliate links might have a teeny one. A really long page with no affiliate links would have a bigger one. And, depending on the look, it will be in different places - sometimes right under the h1 and sometimes under the 1st or second paragraph.

The one I have is called "HTML Snippets" or "XYZ scripts". They seem to interchange these names.