here are a few ModRewrite tips and tricks i suppose, in fairness its more of a reference guide for me when making new rewrite rules than public help docs, but i hope it may help someone somewhere

ReWriteCond Variables

HTTP_USER_AGENT = browser product info

HTTP_ACCEPT = a list of the content types the client will accept

REMOTE_ADDR = THE IP OF THE CLIENT

REMOTE_HOST = THE HOSTNAME OF THE CLIENT

REMOTE_PORT = THE CLIENT TCP PORT WHERE THE CONECTION WAS MADE REMOTE_USER

REMOTE_IDENT

HTTP_PROXY_CONNECTION

HTTP_FORWARD

HTTP_REFERER

HTTP_COOKIE

HTTP_HOST

REQUEST_METHOD

SCRIPT_FILENAME

PATH_INFO

QUERY_STRING

AUTH_TYPE

DOCUMENT_ROOT

SERVER_ADMIN

SERVER_NAME

SERVER_ADDR

SERVER_PORT

SERVER_PROTOCOL

SERVER_SOFTWARE

TIME_YEAR

TIME_MON

TIME_DAY

TIME_HOUR

TIME_MIN

TIME_SEC

TIME_WDAY

TIME = YYYYMMDDHHmmss

API_VERSION = the current version of the api also refered to as the mmn number

THE_REQUEST = the full request sent by the browser

REQUEST_URI = the resource you requested in the http request line

REQUEST_FILENAME = the full path to the filename being requested

IS_SUBREQ = true if request is a sub request

HTTPS = on/off value

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