PMP 

PMP is a performance monitor for remote Windows servers. You can monitor the real time CPU, memory and disk usage status from the several networked servers and can be notified for the specific server status.
performance monitor cpu monitor memory cpu usage memory usage disk usage

EPMon 

Here are some key features of "EPMon": showing the CPU usage of a single process, shows the entire file path of the running programs, auto shutdown function, with an attempt to close the applications gracefully, and more shall come..
epmon cpu usage auto shutdown shutdown net check

DiskAudit 

DiskAudit idenifies the usage of disk space on a multi-user Windows PC. For each user, the program summarizes the total number of files and directories, as well as the total disk space used. Then, the program summarizes disk usage for common folders.
disk audiit disk usage disk utilization ntfs

DiskAudit/2 

DiskAudit/2 identifies the usage of disk space on a multi-user Windows PC. For each user, the program summarizes the total number of files and directories, hidden, system, and common files and folders.
disk audiit disk usage disk utilization ntfs

SimpleActivityLogger 

Log system events such as startup, shutdown, logon, logoff, lock, unlock, StartScreenSaver and StopScreenSaver. Useful for tracking your computer usage during the course of a day for billing purposes or for checking for unauthorised usage.
simpleactivitylogger winlogon notification events lock logoff logon shutdown startscreensaver startshell startup stopscreensaver unlock

statlook 

Cost effective tool kit for software and hardware usage tracking. Delivers detailed statistics on user work time and breaks duration, used applications and web connections. Supporting license compliance. Allows to get a full access to user's computer
asset management user activity license compliance software hardware inventory user activity tracking work time break duration application software usage visited web site history user hard disks computer access control screen capture grabbing