I have been buying and selling loads on ebay recently, it keeps me off mumsnet!
Just got a huge bundle of clothes for ds2, for £1, and felt so guilty I sent her some more money!!
Also have been dealing with some fab sellers, who keep giving me freebies.
Have bought some stuff which I didn't like that much and have sold them for a profit.
I am able to sell stuff for a lot more than if I took it to the 2nd hand shop, but I give my fair share to charity, etc. I don't bother listing things for £1