The Global Trading Station is a building in the current Pokemon games where you can link up to the world of other people who also play and trade Pokemon somewhat discretely. Because you can trade across all current Pokemon games, you would be able to trade a monster that might be pretty common in your game for a rare monster in another game, the trade would make sense to the other person because you monster is pretty rare in his/her game while they only give up a common monster from their game. Another reason you may want to trade is to try and obtain a monster from someone in another country, I am trying to get both a German and Japanese Squirtle (of different genders), Squirtle is pretty easy to get if you already have one because you can breed them and get an Egg that will be a Squirtle. So if this person was lookng for something I put on offer, all they would have to do is make a new Egg and then come back to the GTS and trade - everyone wins! The reason I want to foreign monsters from different counties then my own game pack and each other is because if you breed these two together your new egg has a much higher chance of hatching an alternate color (SUPER RARE) monster, this is not a glitch either, it was a feature built into the game to encourage social play.
SOMEHOW though people are asking for very very very stupid trades while offering NOTHING back, you want a level 1 Squirtle, sure but I want a level 100 Mew in return! What would have been an awesome feature is actually a pretty big hassle now because of people who just ask for impossibilities.
My proposal is that instead of the GTS allowing you to apply filters to the monster you are looking for, but to also put some filters on the monster you are willing to trade. I am looking for [ Squirtle, Female, any level, from Japan] and would trade [ Any Monster, Any Gender, LV 1- 10] - This would enable you to filter out the people looking for level 100 Bidoofs! But it would still allow the level 1 Charizard trades to show up - UNLESS the game had a smart filter on what you could ask for, the game should know you can't get pokes at certain levels and should either deny your request instantly when you put a monster up for trade or AUTOMATICALLY make this trade request invisible to the rest of the world, it should just simply not show up in search results.
Another thing they need to add is a better list interface for viewing potential trades, a scrollbar that can show you all the offers, or a page system with 10 potential trades a page, and if they all suck, then turn to page two to see more trade offers - this alone would at least let you filter through the garbage trades and find legitimate ones, but the way it is now you get a MAXIMUM of only seven trades that show up and let you pick between in an overwhelmingly large percent of the time, impossible trades.
I hope this is fixed with the next generation of games Black and White.
P.S. Oh yeah i also forgot to mention how sometimes you get a monster that is the result of a cheating device and is therefore considered by some people "illegitimate" - like me