HourGlass TM is a date and time simulation tool. Without disrupting other operations on the machine, you can set the date back for your particular login session to, for example, the last day of the last fiscal period in order to re-run certain financial reports. You can also define permanent data or time offsets for particular logons or particular programs or sets of programs. If you have a group of users who log in from a different timezone and want to see their local time on transactions, that's easy to do with HourGlass. Software developers know that date or time specific program bugs are the worst sort because every user will run into them at the same moment, even if they run on different computers.
Installation is simple, and requires only a single re-boot.
Not affected by XNTP or other network time synchronization daemons.