This is just an idea, maybe not even possible, but if it is, I'm sure many many people would want it.
In WoW, you can customize the interface, much like you can now in EQ2, however, I have seen a custom interface set
Cosmos which has an integrated trade window.
From when I was in the WoW beta, it was awesome, you just have to have the item in your inventory, you then opened up a custom window, selected an item, and set your prices, then it would broadcast the item into its own special chat channel, which only people who were using the mod would be able to see, and you could bid on it. Then when you won the item, you would contact the seller, meet, purchase, and be done with it.
Sitting in your house all selling and stuff is beat. I'd love, literally would probably donate either time, resources, knowledge, maybe even money, into seeing someone develop something like this.
What does everyone else think?