Formatting

[b]bold text[/b] Bold text
[u]underline text[/u] Underline text
[i]italic text[/i] Italic text
[s]strikethrough text[/s] Strikethrough text
[center]center align[/center] Center aligns text/images
[colour=COLOUR-CODE]coloured text[/colour] Colours text
[color=COLOR-CODE]colored text[/color] Colors text
[url=WEB-ADDRESS]link title[/url] Link with title
[url]WEB-ADDRESS[/url] Link with no title

Objects

[user]USER-ID[/user] User status tag
[img]IMAGE-ADDRESS[/img] Image/picture
[youtube]YOUTUBE-CODE[/youtube] YouTube video
To find the YouTube Code of a video, it is the part shown highlighted below:
http://www.youtube.com/watch?v=3dqsyXPkG3I&feature=related

Smilies

:alien: :brainwash:
:cool: :cry:
:delight: :eek:
:erm: :evil:
:facepalm: :fat:
:freeze: :fury:
:haha: :heh:
:hmm: :ice:
:jawdrop: :kiss:
:mad: :mwah:
:nut: :rasberry:
:razz: :rolleyes:
:sad: :scared:
:scream: :shifty:
:shock: :shy:
:sick: :smile:
:tongue: :weh:
:wink: :shoopdawhoop:
:fistpump: