Advanced Registry Tracer (ART; formely RegFix) is an utility designed for analyzing the changes made to Windows Registry - by making the snapshots of it and keeping them in the browsable database. You can compare any two snapshots and get the list of keys/data which are new, deleted or just changed. ART can do comparing not only in the entire Regisrty, but also in any key of the Registry. It is also possible to exclude any keys of the Registry from compare results. Moreover, you can create undo/redo files (for example, to rollback the changes). To view the current state of a key, or to modify it, you can use Jump to Regedit function. Contents of any key can be exported to *.reg file.
Very useful for detecting trojan viruses and elimination some problems caused by software and hardware install/uninstall.

Limitations: 30-day trial.