What did you play on it?
Any of Horowitz stuff?
So far I only know one piece on the piano

Just really got started with it. So I played it over and over and over... and after about half and hour they kicked me off it, because some steinway artist showed up and wanted to warm up on the piano in preparation for the concert that night.
I played the Debussy Arabesque #1. I made a little recording of the Debussy on my own Steinway at home and it's in the "audition room" message board. Listen at your own risk. I recorded it on the yamaha electric piano too.
I wish I could play some Horowitz stuff! Maybe someday. I'm still trying to work on the Arabesque. I'll record it again when I get better at it and maybe post it here.
But now I'm learning another piece. Bach invention #1. And also started fooling around with other pieces! Piano is so much fun. I really should be spending time with my violin, but ahhh.. the piano... I wonder why I never picked it up when I was younger. The piano definitely cuts into my violin time. But it's worth it.