Listening to Mozart's Piano Concerto No. 20 in D minor is one of my favourite pieces to program against. Whenever I need to do some serious programming I just search for some performances on Youtube and code away.
It just struck me that although it is one of my favourite pieces, I never have seen an actual performance live. Is there an online resource (similar to Operabase), where you can search for a given concerto being performed somewhere in the world? I have search a bit, but usually the search options are concert hall driven. Here I want to travel somewhere the piece is actually being performed soon.