What magic?

Ever get tired of typing :D, only to find ( ^^ ) staring you down once you hit submit? Or how about :X becoming ( >_^< )? Are you wondering how I managed to type up that example without its own point thwarting me? Well, here's the secret:

:<b></b>D

YES! IT IS THAT SIMPLE!

Now, all of you, stop whining that dA stole your ability to use your favourite smiley. There's no longer any need for your complaining.

Note: You could also use <a></a>, <i></i>, <u></u>, or even <abbr></abbr>. Any closing-tag-dependent HTML tag would work.

Is that all this is good for?

Absolutely not! Just look around! You can use this method to get around just about any code that deviantART's parsing system renders differently.
For example: my, well, examples! How did I get "<b></b>" to render that way?

<<b></b>b><<b></b>/b>

Want to type a URL without it becoming "[link]"?

http://www.example.com
http://<b></b>www.<b></b>example.com

This particular example comes in handy if you're ever giving somebody a chat log or anything of that sort. Let them know what was really said!

http://www.example.com

Another use: Teaching deviants to use devART codes.
I personally think "Just type :*hmm*: without the asterisks." looks simply hideous. Doesn't "Just type :hmm:." look loads nicer and more professional?
How about this:

*username

Annoying, right?
Using this trick, you can properly tell somebody how to use :icon: and :dev: codes:

:devusername: :iconusername:
:dev<b></b>username: :icon<b></b>username:

Okay... Why does this work?

Well, when you send a packet of data to deviantART, it goes through and searches the incoming source code for certain sequences, such as emoticon codes, and so, obviously, when it sees ":<b></b>D", it doesn't think of ":D". Then, after it's swept through and caught the emoticon codes, it searches again for HTML, at which point the "<b></b>" is stripped. So, in the end, you get ":D".

_{Disclaimer: This section was, for the most part, guess work. I could be wrong, but it's just technical jargon; who cares? :U}