Textile

HTML

h3{margin-top:0}. Your cart

* Item one
* Item two

More about: HTML

1. To prevent Textile from enclosing complex HTML blocks in paragraph tags, either use a space at the beginning of each line:

 <div>
    <span>My div</span>
 </div>

Or a notextile.. extended block:

notextile.. <div>
    <span>My div</span>
</div>

2. HTML comments are respected as comments:

Here is some text with a <!-- Commented out[1] --> block.

<!-- Here is a single <span>line</span> comment block -->

<!-- Here is a whole
multiline
<span>HTML</span>
Comment
-->

3. Unicode symbols can be entered in decimal form, like this:

p{font-size:20pt;}. ☢ ☁ ♘

With a browser that is capable, and a font that supports the characters, you will see this:

☢ ☁ ♘

Further reading: HTML

1. MDN: HTML elements reference
2. Emoticons Unicode (Wikipedia)
3. Unicode (Wikipedia)
4. Unicode Character Code Charts