Xteq X-Setup : Allows you to change settings that are normally hidden deeply in Windows. It also has plugin capabilities to allow new settings. The official version is now shareware, but the link here leads to the last available free version. The company who produced this went under, but as a thank you to all their users, they provided a serial that can be used on the last released version, available at the above link.
TaskBan : TaskBan is a replacement for the standard Task Manager (TASKMAN.EXE) which ships with Windows 95-98SE. This is a great program for those of you still stuck on Win98SE and previous. (Again, thank you Wayback Machine!)