Can I get Exchange management functionality on a computer without installing Exchange System Manager (ESM)?

Yes, you can add Exchange management functionality in a roundabout way. Maildsmx.dll implements the Exchange tabs that you see when you open the Microsoft Management Console (MMC) Active Directory Users and Computers snap-in. As a result, if you copy this .dll file to the target machine and use regsvr32.exe to register the file, you'll be partway there. You'll need to also copy and register escprint.dll, address.dll, and exchmem.dll.