Go to the migros bank at limmatplatz, they've got a machine there right insisde the door and it couldnt be easier. As I recall its also open on saturday mornings, although I appreciated I'm 10 hours late telling you this. You dont even have to sort the coins out into different types, you just pour them in the top and then, if you're like me, wait an embarassingly long amount of time as it counts them all out.

440.- to beat!