Site Statistics:-
$totalthreads - Displays the total number of threads in the forum
      $totalposts - Displays total number of posts in the forum
      $numbermembers - Display total number of members in the forum
      $totalonline - Displays the number of total users currently online
      $numberregistered - Displays the number of total registered users currently online
      $numberguest - Displays the number of total guests currently online
      $recordusers - Displays the number of most users ever online
      $recorddate - Displays the date on which most users were ever online
      $recordtime - Displays the time on which most users were ever online
      $activeusers - Displays a list of currently active/online Users (i.e. logged in)
      $activemembers - Displays the number of members who are active in the forum
      $newusername - Displays the username of the newly registered user
      $birthdays - Displays list of users whose birthday is today
      $upcomingevents - Displays list of upcoming events

$BBuserinfo Array, this can show anything thats stored in the user table

$bbuserinfo[username] - Username
$bbuserinfo[userid] - User ID number
$bbuserinfo[posts] - Users postcount
$bbuserinfo[signature] - Users signature
$bbuserinfo[email] - User Email Address
$bbuserinfo[homepage] - Users homepage in profile
$bbuserinfo[msn] - Users MSN address from profile
$bbuserinfo[yahoo] - "" Yahoo ""
$bbuserinfo[icq] - "" ICQ ""
$bbuserinfo[usertitle] - Users custom usertitle

$VBoptions Array, these are the options stored in the settings table, i.e things that you configured from vbulletin AdminCP>>vbulletin Options.
      $vboptions[forumactive] - Status of whether forum is turned on/off
      $vboptions[bbclosedreason] - Reason why forum turned off
      $vboptions[bbtitle] - Forum title
      $vboptions[bburl] - Forum URL
      $vboptions[hometitle] - Site homepage Title
      $vboptions[homeurl] - Site homepage URL
      $vboptions[copyrighttext] - Site copyright text
      $vboptions[privacyurl] - URL to forum privacy statement
      $vboptions[webmasteremail] - Webmaster email address
      $vboptions[contactuslink] - contact us URL
      $vboptiions[enablehooks] - Status of plugin/hook system
      $vboptions[imagetype] - Determine if using GD or Imagemagick
      $vboptions[timeoffset] - forum time offset
      $vboptions[cookiepath] - forum cookie path
      $vboptions[legacypostbit] - Determine if using legacy (side) postbit or new horizontal postbit
      $vboptions[use_smtp] - If SMTP mail is enabled
      $vboptions[smtp_host] - SMTP hostname
      $vboptions[smtp_port] - SMTP port number
      $vboptions[allowregistrations] - Determine if new users can register
      $vboptions[welcomemail] - Determine if welcome mail is sent on registration
      $vboptions[avatarenabled] - Check if avatars are enabled
      $vboptions[reputationenable] - Check if reputation system is enabled
$stylevar Array, this contains all the paths to forum images and other style variables that are editable in the Styles and templates >> Stylevars
     $stylevar[titleimage] - Path/filename for top banner
      $stylevar[outertablewidth] - The width of your forum
      $stylevar[spacersize] - Spacing betwen main body and content
      $stylevar[cellspacing] - Inner border width
      $stylevar[cellpadding] Table cell padding
      $stylevar[formwidth] - Form width in pixels
      $stylevar[imgdir_buton] - Path for forum buttons
      $stylevar[imgdir_statusicon] - Path for status icons
      $stylevar[imgdir_attach] - Path for attachment icons

$css array, this is where all the CSS attributed can be located
      $css variables[body][background] - Body background colour
      $css[body][color] - Body text colour
      $css[body][LINK_N][color] - Body normal links
      $css[body][LINK_V][color] - Body visited links
      $css[body][LINK_M][color] - Body link hover colour
      $css[.page][background] - Page background colour
      $css[.page][color] - Page text colour
      $css[.tborder][background] - Table border background colour
      $css[.tborder][color] - Table border font colour
      $css[.tcat][background] - Category strip background/colour
      $css[.tcat][color] - Category strip font colour
      $css[.thead][background] - Table header background gradient/colour
      $css[.thead][color] - Table header background colour
      $css[.tfoot][background] - Table footer background colour/gradient
      $css[.tfoot][color] - Table footer text colour

Ad Location Template variables:-
$ad_location[ad_footer_end] - Displays content of ad_footer_end template
      $ad_location[ad_footer_start] - Displays content of ad_footer_start template
      $ad_location[ad_forumdisplay_afterthreads] - Displays content of ad_forumdisplay_afterthreads template
      $ad_location[ad_forumdisplay_afterforums] - Displays content of ad_forumdisplay_afterforums template
      $ad_location[ad_header_logo] - Displays content of ad_header_logo template
      $ad_location[ad_header_end] - Displays content of ad_header_end template
      $ad_location[ad_navbar_below] - Displays content of ad_navbar_below template
      $ad_location[ad_showthread_beforeqr] - Displays content of ad_showthread_beforeqr template
      $ad_location[ad_showthread_firstpost] - Displays content of ad_showthread_firstpost template


Miscellenous:-
$notices - Used to display notices (for 3.7 onwards)
      $notifications_total - Used to display total number of unread notifications (for 3.7 onwards)