It consists of a vast amount of DVDs - most of which are staying as we love movies/cartoons/comedy etc.
Loads of toys especially little extras for Lego, Playmobil, train set etc, character figures, jigsaws.
Some books although I'd reduced them a while back, I hardly ever buy due to working in a huge library, loads of kids books though especially my old favourites which are out of print.
A few house/health items that aren't available locally (eg Epsom salts to use for pain relief)
Board/video games, some music although that has also been reduced now I use iTunes.
Loads of books, DVDs etc I think of as presents for family.
Geeky tshirts and a few other clothes.
Christmassy bits and bobs like nice stockings.
So... yeah. A fair bit. 
My problem is I tend to use Amazon as my first port of call, any time something is recommended on MN I add it, and stuff that comes up on the 'also bought' bit... Rather than making a decision there and then I just add all of it. It's part of a bigger issue of not wanting to miss out on anything, I'm very "all or nothing" if that makes sense.
Making vast improvements though and looking forward to seeing how much I delete!