I've gone a bit ikea mad in ours!
We had lots of Billy bookcases which are great for books but not deep enough to hold board games, toys etc so I got the expedit shelves.
They're great, they do a whole range of different boxes to fit them. You can also buy doors and internal shelves for them too.
I got some black open top boxes and some cream leather type with lids and then left some of the shelves empty so toys can for in them.
Each dc has their own shelf and their own box. Their favourite at the moment toys, comics etc go in them. Also their bookbags from school.
I've also got 2 sets of shelves with 9 small wicker baskets in each. Great for storing toy cars, play food and tea sets, barbie, happy land people etc.
I took out the shelves from the Billy bookcases and tipped them onto their sides. The tv, wii, kinect are on the top of them and then long open shelves underneath hold books. Anything gaming goes on the top shelf so we never lose controllers, chargers etc. I have a small storage shelf for keeping the xbox wii DS games on.
Oldest dc is 14, youngest 11 months with a 5 and 7 year old in the middle so deciding on how to decorate it was tricky.
I've gone for 2 white walls, 2 turquoisey walls. All shelves white. Brown leather sofa. Beige cushions at the moment but i got some black material, with red, green etc pattern , ikea again(!) that I'm going to make new covers with. Some chairs in red. Some in white. White rug with bold red, blue, yellow, green pattern on it.
Cream bean bags. 2 huge mirrors.
The majority of the furniture and furnishing is from ikea.
I rotate the toys every couple of months from their bedrooms and find that they play with stuff more.
It's child friendly enough to spend the day in there with the youngest but everything has a place and can be packed away so that the oldest can have his friends over in the evening and not feel like he is in a baby room.
In the front room I have one small domestic science school type basket tucked down the side of the sofa with baby toys in it.