re task manager. Quick and simple way which doesnt involving installing anything is going to a x terminal window and typing 'top'.

This is the busybox version of top, so its cut right back in features and only seems to accept 'q' as a keystroke which quits top.

If you want to kill a process (careful here) you can type 'kill <pid>' in a terminal window, replacing <pid> with the process id number, which you can get from top.

hope that helps