The PsGetsid application was developed to be a small tool that will allow you to translate SIDs to their display name and vice versa. It works on builtin accounts, domain accounts, and local accounts.
Usage:
psgetsid [\\computer[,computer[,...] | @file] [-u username [-p password]]] [account|SID]
If you want to see a computer's SID just pass the computer's name as a command-line argument. If you want to see a user's SID, name the account (e.g. "administrator") on the command-line and an optional computer name.
Specify a user name if the account you are running from doesn't have administrative privileges on the computer you want to query. If you don't specify a password as an option, PsGetSid will prompt you for one so that you can type it in without having it echoed to the display.