And ours isn't even finished. But it's about 1000 square feet of open space, and it's not too chilly down there either.
We have some boxes being stored down there, and we also put a lot of our big huge movement toys there. Big bouncy balls, beach balls, the PowerWheels VW, the ride on toys, etc. Yuta showed Taipan his officially licensed light sabers earlier in the week too, and we've been re-enacting Star Wars battles for hours each day. We've got a double-sided Darth Maul light saber, and a green and a red one. They're too big for playing upstairs, and the basement is perfect for them. Our favorite battle comes from Episode I, Chapter 6: Darth Maul. We take turns on who gets who, and sometimes we'll need a droid, so we alternate being R2 and C3PO.
Since we didn't need our big shag rug in the house, we put that on the basement floor so there's a comfy place to sit. We played on the rug for a bit last night too.
I've been anxious and in a hurry to get the basement finished. We know it won't happen any time soon unless we get some unexpected cash, and after the play we've done down there this week I don't think it's so bad to wait and have it finished later.