There are none. The only way would either be with another computer or, more feasible, would be Virtual Machines. With VMWare or someting of that nature, you could have five, six, seven ACs open at the same time. Just have to keep in mind that you must pay for a license for each OS, which could be rather costly.
But, on one computer with one OS, you can only open one chart. You can, however use CTRL - S to save a chart instantly to your inbox.
