Sure, you guys might know /tell or /g, but do you know the whole list?

Here's some lesser-known commands:

/ignore - ignores users

/g or /guild - guild chat

/invite - invites a player to your party, provided that they are online

/bug - reports a bug to the GM's.

/joinknight - joins the specified player, provided that they have enough room

/r - replies to a /tell or /whisper

/o - guild officers chat

/afk - automatically sends a message to players trying to /tell you that you are currently AFK

/complain or /report - the best way to file a complaint (the best part is that they don't even have to be next to you)