This add-on allows you to read trade chat even when you aren't inside a city.
Granted, it only works if someone else who has the add-on is currently in a city, but in a high population server that shouldn't be a problem at all. When in doubt, ask your entire guild to install it
"/wtc on" - activate
"/wtc off" - decativate
"/wtc chatframe X" - make the add-on write to a different chat frame instead of the default one (replace X with chat frame number of your choice)
This add-on was originally made by yylang1987 and released here under MIT license. It does not seem to be maintained, so I took the liberty of adding features and republishing.
Have you seen my other add-ons yet? SanityCheck - Of course you know how to play your class, but there is just so much to remember! Raidbot - The right way to raid! Flaskaholic - Flasks are expensive, stop wasting them! Surprise - Guaranteed to make you smile after you kill Garrosh Hellscream, or your money back! MooTrack - The simple, lightweight way to keep track of buffs and debuffs! MagicMarker - One configurable tool for all your automatic marking needs!