I have around 1500. I have been collecting them since day one. I haven't been getting many lately because I record those I get from the library on blanks. I store them in milk crates and have 7 crates full with another 400 or so in CD containers.
I have around 700-800. Started buying them young in the early 90's. I've been slowly giving some away and selling others as I have run out of space and have no more room for them.