I can really recommend the Billy bookcases. Except for one that fell over during a move and important parts of it broke (it was a tall, wide one, it had glass doors on it, and the glass door got wrenched which ripped off part of the side "wall" of the unit), we've had our Billy shelves for years.
Many people avoid the lower-end of the cost spectrum *couches*, because they don't last that long. I have never had an Ikea couch so I have no experience in that.
We bought a mattress from them, and while it didn't work out for us, their great warranty on mattresses did.
And everything else there is just fun. They have their new "Ikea family" program which gives a few extra discounts, a free frozen yogurt (we can't have it b/c of corn syrup, sadness), free coffee at the restaurant, etc.