First, on XP, you usually don't need any special programs to map other computer's drives, however, you do need a user account with the right privileges on the computer that has the drive you are trying to connect to. If you are attempting to connect to a Windows server's drive, you'll need to make sure that the user's NTFS permissions on the server along with the group policy settings, it's best to create a "share" sub-group then add the users main group to the share group (You can only add a group to a group on Windows Servers, then add the share group to logon over network and log on locally, also disable simple file sharing (servers, 2000 pro, xp pro only).
Anyway, back to XP pro, simply go to My Computer, click on Tools, the first option is Map Network Drive.
There is a bug about XP remembering passwords, so I don't check the remember box, however, when you go to map a drive, look for a box that says "Reconnect at Logon" and simply check that box, and once that box is checked, don't also check the remember password box when entering username and password. When checking Reconnect at Logon, Windows automatically remembers the username and password.
As for connecting over the internet, I wouldn't advise it, as you would most likely have to enable NetBios Over TCP/IP which is a security risk as well as having to configure Port Forwarding on the computer's router that has the shared drive.
Also, I don't know about Vista or other versions of XP other then pro and Win 2000 pro but those OS's by default already have shared drives configured for admins which are called Administrative Shares, which is notated by the real physical drive letter followed by a $, you usually need admin rights on the computer your connecting to to use these shares though.
If you are connecting from a computer that has the capability to disable simple file sharing you would get the whole drive with full admin rights to the folder. Otherwise you'll only see publicly available shares.
Also, the $ can be used to hide the share name, example, if you share a folder on one computer and give it the sharename myfolder$, it can only be accessed by direct path as the name won't show up in the shared list.
Maybe this will help some of you out.
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