The person who wrote that this application is "silly" obviously doesn't understand how incredibly useful this application is to people who want ONE OS X user account so that they can share the same iPhoto, iTunes, Address Book, etc. -- BUT who simply want two or more users for Mail.app. This application fill the bill perfectly and is well worth $10! It goes on my VERY short list of applications that are extremely useful for the typical home user and that fill major holes in the OS (others include iDress and iPhoto Library Manager. This already deserves five stars, but my suggestions for further improvement are: (1) revise the instructions to provide better explanation to "newbies" of how to reconfigure existing Mail.app accounts under another user into one user; (2) perhaps even provide some sort of automated "import" function that takes care of all settings (if that's even possible); (3) provide for payment by PayPal if feasible; (4) create a menu bar button so that Mailswitch can be even more easily accessed. These are all just personal suggestions, though: the program works great as is. Thank you! -- and shame on any unthinking critics who call the idea behind the app silly.